diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rewrite/PropertiesRewritePolicy.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rewrite/PropertiesRewritePolicy.java
index f0e40a7..3ef6b6d 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rewrite/PropertiesRewritePolicy.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rewrite/PropertiesRewritePolicy.java
@@ -67,7 +67,7 @@ public final class PropertiesRewritePolicy implements RewritePolicy {
         for (final Map.Entry<Property, Boolean> entry : properties.entrySet()) {
             final Property prop = entry.getKey();
             props.put(prop.getName(), entry.getValue().booleanValue() ?
-                config.getStrSubstitutor().replace(prop.getValue()) : prop.getValue());
+                config.getStrSubstitutor().replace(config, prop.getValue()) : prop.getValue());
         }
 
         final LogEvent result = new Log4jLogEvent.Builder(source).setContextMap(props).build();
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/DefaultRolloverStrategy.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/DefaultRolloverStrategy.java
index e014bd7..c2d7dac 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/DefaultRolloverStrategy.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/DefaultRolloverStrategy.java
@@ -293,8 +293,8 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
         final StringBuilder buf = new StringBuilder();
 
         // LOG4J2-531: directory scan & rollover must use same format
-        manager.getPatternProcessor().formatFileName(subst, buf, highIndex);
-        String highFilename = subst.replace(buf);
+        manager.getPatternProcessor().formatFileName(null, subst, buf, highIndex);
+        String highFilename = subst.replace(null, buf);
         final int suffixLength = suffixLength(highFilename);
         int maxIndex = 0;
 
@@ -344,9 +344,9 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
                 // add a rename action to the list
                 buf.setLength(0);
                 // LOG4J2-531: directory scan & rollover must use same format
-                manager.getPatternProcessor().formatFileName(subst, buf, i - 1);
+                manager.getPatternProcessor().formatFileName(null, subst, buf, i - 1);
 
-                final String lowFilename = subst.replace(buf);
+                final String lowFilename = subst.replace(null, buf);
                 String renameTo = lowFilename;
 
                 if (isBase) {
@@ -358,9 +358,9 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
             } else {
                 buf.setLength(0);
                 // LOG4J2-531: directory scan & rollover must use same format
-                manager.getPatternProcessor().formatFileName(subst, buf, i - 1);
+                manager.getPatternProcessor().formatFileName(null, subst, buf, i - 1);
 
-                highFilename = subst.replace(buf);
+                highFilename = subst.replace(null, buf);
             }
         }
         if (maxIndex == 0) {
@@ -400,9 +400,9 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
         final StringBuilder buf = new StringBuilder();
 
         // LOG4J2-531: directory scan & rollover must use same format
-        manager.getPatternProcessor().formatFileName(subst, buf, lowIndex);
+        manager.getPatternProcessor().formatFileName(null, subst, buf, lowIndex);
 
-        String lowFilename = subst.replace(buf);
+        String lowFilename = subst.replace(null, buf);
         final int suffixLength = suffixLength(lowFilename);
 
         for (int i = lowIndex; i <= highIndex; i++) {
@@ -445,9 +445,9 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
                 // add a rename action to the list
                 buf.setLength(0);
                 // LOG4J2-531: directory scan & rollover must use same format
-                manager.getPatternProcessor().formatFileName(subst, buf, i + 1);
+                manager.getPatternProcessor().formatFileName(null, subst, buf, i + 1);
 
-                final String highFilename = subst.replace(buf);
+                final String highFilename = subst.replace(null, buf);
                 String renameTo = highFilename;
 
                 if (isBase) {
@@ -512,7 +512,7 @@ public class DefaultRolloverStrategy implements RolloverStrategy {
             LOGGER.trace("DefaultRolloverStrategy.purge() took {} milliseconds", durationMillis);
         }
         final StringBuilder buf = new StringBuilder(255);
-        manager.getPatternProcessor().formatFileName(subst, buf, fileIndex);
+        manager.getPatternProcessor().formatFileName(null, subst, buf, fileIndex);
         final String currentFileName = manager.getFileName();
 
         String renameTo = buf.toString();
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/PatternProcessor.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/PatternProcessor.java
index af5bcdb..dda94f0 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/PatternProcessor.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/PatternProcessor.java
@@ -24,6 +24,7 @@ import java.util.List;
 
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.impl.Log4jLogEvent;
 import org.apache.logging.log4j.core.lookup.StrSubstitutor;
 import org.apache.logging.log4j.core.pattern.ArrayPatternConverter;
@@ -206,13 +207,13 @@ public class PatternProcessor {
      * @param buf string buffer to which formatted file name is appended, may not be null.
      * @param obj object to be evaluated in formatting, may not be null.
      */
-    public final void formatFileName(final StrSubstitutor subst, final StringBuilder buf, final Object obj) {
+    public final void formatFileName(final Configuration config, final StrSubstitutor subst, final StringBuilder buf, final Object obj) {
         // LOG4J2-628: we deliberately use System time, not the log4j.Clock time
         // for creating the file name of rolled-over files. 
         final long time = prevFileTime == 0 ? System.currentTimeMillis() : prevFileTime;
         formatFileName(buf, new Date(time), obj);
         final LogEvent event = new Log4jLogEvent.Builder().setTimeMillis(time).build();
-        final String fileName = subst.replace(event, buf);
+        final String fileName = subst.replace(config, event, buf);
         buf.setLength(0);
         buf.append(fileName);
     }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/AbstractPathAction.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/AbstractPathAction.java
index e66f543..6606eb5 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/AbstractPathAction.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/rolling/action/AbstractPathAction.java
@@ -103,7 +103,7 @@ public abstract class AbstractPathAction extends AbstractAction {
      * @return the base path (all lookups resolved)
      */
     public Path getBasePath() {
-        return Paths.get(subst.replace(getBasePathString()));
+        return Paths.get(subst.replace(null, getBasePathString()));
     }
 
     /**
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/routing/RoutingAppender.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/routing/RoutingAppender.java
index a6b5df0..96872ac 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/routing/RoutingAppender.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/appender/routing/RoutingAppender.java
@@ -111,7 +111,7 @@ public final class RoutingAppender extends AbstractAppender {
         if (rewritePolicy != null) {
             event = rewritePolicy.rewrite(event);
         }
-        final String key = config.getStrSubstitutor().replace(event, routes.getPattern());
+        final String key = config.getStrSubstitutor().replace(config, event, routes.getPattern());
         final AppenderControl control = getControl(key, event);
         if (control != null) {
             control.callAppender(event);
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/async/AsyncLogger.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/async/AsyncLogger.java
index 226ba08..167bb00 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/async/AsyncLogger.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/async/AsyncLogger.java
@@ -345,7 +345,7 @@ public class AsyncLogger extends Logger implements EventTranslatorVararg<RingBuf
      */
     public void actualAsyncLog(final RingBufferLogEvent event) {
         final Map<Property, Boolean> properties = privateConfig.loggerConfig.getProperties();
-        event.mergePropertiesIntoContextMap(properties, privateConfig.config.getStrSubstitutor());
+        event.mergePropertiesIntoContextMap(privateConfig.config, properties, privateConfig.config.getStrSubstitutor());
         final ReliabilityStrategy strategy = privateConfig.loggerConfig.getReliabilityStrategy();
         strategy.log(this, event);
     }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/async/RingBufferLogEvent.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/async/RingBufferLogEvent.java
index a78582f..c6e901c 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/async/RingBufferLogEvent.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/async/RingBufferLogEvent.java
@@ -24,6 +24,7 @@ import org.apache.logging.log4j.Level;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.ThreadContext.ContextStack;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.Property;
 import org.apache.logging.log4j.core.impl.Log4jLogEvent;
 import org.apache.logging.log4j.core.impl.ThrowableProxy;
@@ -294,8 +295,8 @@ public class RingBufferLogEvent implements LogEvent {
      * @param properties configured properties
      * @param strSubstitutor used to lookup values of variables in properties
      */
-    public void mergePropertiesIntoContextMap(final Map<Property, Boolean> properties,
-            final StrSubstitutor strSubstitutor) {
+    public void mergePropertiesIntoContextMap(final Configuration config, final Map<Property, Boolean> properties,
+                                              final StrSubstitutor strSubstitutor) {
         if (properties == null) {
             return; // nothing to do
         }
@@ -308,7 +309,7 @@ public class RingBufferLogEvent implements LogEvent {
             if (map.containsKey(prop.getName())) {
                 continue; // contextMap overrides config properties
             }
-            final String value = entry.getValue().booleanValue() ? strSubstitutor.replace(prop.getValue()) : prop
+            final String value = entry.getValue().booleanValue() ? strSubstitutor.replace(config, prop.getValue()) : prop
                     .getValue();
             map.put(prop.getName(), value);
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/ConfigurationFactory.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/ConfigurationFactory.java
index 8f3d764..b3604b3 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/ConfigurationFactory.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/ConfigurationFactory.java
@@ -389,7 +389,7 @@ public abstract class ConfigurationFactory extends ConfigurationBuilderFactory {
         public Configuration getConfiguration(final String name, final URI configLocation) {
 
             if (configLocation == null) {
-                final String configLocationStr = this.substitutor.replace(PropertiesUtil.getProperties()
+                final String configLocationStr = this.substitutor.replace(null, PropertiesUtil.getProperties()
                         .getStringProperty(CONFIGURATION_FILE_PROPERTY));
                 if (configLocationStr != null) {
                     ConfigurationSource source = null;
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/LoggerConfig.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/LoggerConfig.java
index ee100b4..8285aba 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/LoggerConfig.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/LoggerConfig.java
@@ -332,7 +332,7 @@ public class LoggerConfig extends AbstractFilterable {
             LogEvent event = builder.build();
             for (final Map.Entry<Property, Boolean> entry : properties.entrySet()) {
                 final Property prop = entry.getKey();
-                final String value = entry.getValue() ? config.getStrSubstitutor().replace(event, prop.getValue())
+                final String value = entry.getValue() ? config.getStrSubstitutor().replace(config, event, prop.getValue())
                         : prop.getValue();
                 props.add(Property.createProperty(prop.getName(), value));
             }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/json/JsonConfiguration.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/json/JsonConfiguration.java
index fcde1d5..87a3198 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/json/JsonConfiguration.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/json/JsonConfiguration.java
@@ -71,7 +71,7 @@ public class JsonConfiguration extends AbstractConfiguration implements Reconfig
                     .withStatus(getDefaultStatus());
             for (final Map.Entry<String, String> entry : rootNode.getAttributes().entrySet()) {
                 final String key = entry.getKey();
-                final String value = getStrSubstitutor().replace(entry.getValue());
+                final String value = getStrSubstitutor().replace(this, entry.getValue());
                 // TODO: this duplicates a lot of the XmlConfiguration constructor
                 if ("status".equalsIgnoreCase(key)) {
                     statusConfig.withStatus(value);
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginAttributeVisitor.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginAttributeVisitor.java
index f4da42b..576bddf 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginAttributeVisitor.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginAttributeVisitor.java
@@ -40,7 +40,7 @@ public class PluginAttributeVisitor extends AbstractPluginVisitor<PluginAttribut
         final String name = this.annotation.value();
         final Map<String, String> attributes = node.getAttributes();
         final String rawValue = removeAttributeValue(attributes, name, this.aliases);
-        final String replacedValue = this.substitutor.replace(event, rawValue);
+        final String replacedValue = this.substitutor.replace(configuration, event, rawValue);
         final Object defaultValue = findDefaultValue(event);
         final Object value = convert(replacedValue, defaultValue);
         final Object debugValue = this.annotation.sensitive() ? NameUtil.md5(value + this.getClass().getName()) : value;
@@ -76,6 +76,6 @@ public class PluginAttributeVisitor extends AbstractPluginVisitor<PluginAttribut
         if (this.conversionType == Class.class) {
             return this.annotation.defaultClass();
         }
-        return this.substitutor.replace(event, this.annotation.defaultString());
+        return this.substitutor.replace(null, event, this.annotation.defaultString());
     }
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginBuilderAttributeVisitor.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginBuilderAttributeVisitor.java
index e951456..6b15e12 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginBuilderAttributeVisitor.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginBuilderAttributeVisitor.java
@@ -46,7 +46,7 @@ public class PluginBuilderAttributeVisitor extends AbstractPluginVisitor<PluginB
         final String name = overridden.isEmpty() ? this.member.getName() : overridden;
         final Map<String, String> attributes = node.getAttributes();
         final String rawValue = removeAttributeValue(attributes, name, this.aliases);
-        final String replacedValue = this.substitutor.replace(event, rawValue);
+        final String replacedValue = this.substitutor.replace(configuration, event, rawValue);
         final Object value = convert(replacedValue, null);
         final Object debugValue = this.annotation.sensitive() ? NameUtil.md5(value + this.getClass().getName()) : value;
         StringBuilders.appendKeyDqValue(log, name, debugValue);
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginValueVisitor.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginValueVisitor.java
index 5ec53da..bd2fca2 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginValueVisitor.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/plugins/visitors/PluginValueVisitor.java
@@ -37,7 +37,7 @@ public class PluginValueVisitor extends AbstractPluginVisitor<PluginValue> {
         final String name = this.annotation.value();
         final String rawValue = node.getValue() != null ? node.getValue() :
             removeAttributeValue(node.getAttributes(), "value");
-        final String value = this.substitutor.replace(event, rawValue);
+        final String value = this.substitutor.replace(configuration, event, rawValue);
         StringBuilders.appendKeyDqValue(log, name, value);
         return value;
     }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/xml/XmlConfiguration.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/xml/XmlConfiguration.java
index 4369b89..16c7a7a 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/config/xml/XmlConfiguration.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/config/xml/XmlConfiguration.java
@@ -112,7 +112,7 @@ public class XmlConfiguration extends AbstractConfiguration implements Reconfigu
                     .withStatus(getDefaultStatus());
             for (final Map.Entry<String, String> entry : attrs.entrySet()) {
                 final String key = entry.getKey();
-                final String value = getStrSubstitutor().replace(entry.getValue());
+                final String value = getStrSubstitutor().replace(this, entry.getValue());
                 if ("status".equalsIgnoreCase(key)) {
                     statusConfig.withStatus(value);
                 } else if ("dest".equalsIgnoreCase(key)) {
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/AbstractLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/AbstractLookup.java
index 1dba499..3caf6c6 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/AbstractLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/AbstractLookup.java
@@ -16,6 +16,8 @@
  */
 package org.apache.logging.log4j.core.lookup;
 
+import org.apache.logging.log4j.core.config.Configuration;
+
 /**
  * A default lookup for others to extend.
  * 
@@ -26,11 +28,11 @@ public abstract class AbstractLookup implements StrLookup {
     /**
      * Calls {@code lookup(null, key)} in the super class.
      * 
-     * @see StrLookup#lookup(LogEvent, String)
+     * @see StrLookup#lookup(Configuration, org.apache.logging.log4j.core.LogEvent, String)
      */
     @Override
-    public String lookup(final String key) {
-        return lookup(null, key);
+    public String lookup(final Configuration config, final String key) {
+        return lookup(config, null, key);
     }
 
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ContextMapLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ContextMapLookup.java
index 9a39338..3670aeb 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ContextMapLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ContextMapLookup.java
@@ -18,6 +18,7 @@ package org.apache.logging.log4j.core.lookup;
 
 import org.apache.logging.log4j.ThreadContext;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 
 /**
@@ -28,22 +29,24 @@ public class ContextMapLookup implements StrLookup {
 
     /**
      * Looks up the value from the ThreadContext Map.
+     * @para config The Configuration for which the lookup is being attempted
      * @param key  the key to be looked up, may be null
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         return ThreadContext.get(key);
     }
 
     /**
      * Looks up the value from the ThreadContext Map.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent.
      * @param key  the key to be looked up, may be null
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         return event.getContextMap().get(key);
     }
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/DateLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/DateLookup.java
index 3e630b0..64f56c1 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/DateLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/DateLookup.java
@@ -24,6 +24,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.status.StatusLogger;
 
@@ -38,22 +39,24 @@ public class DateLookup implements StrLookup {
 
     /**
      * Looks up the value of the environment variable.
+     * @param config The Configuration for which the lookup is being attempted
      * @param key the format to use. If null, the default DateFormat will be used.
      * @return The value of the environment variable.
      */
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         return formatDate(System.currentTimeMillis(), key);
     }
 
     /**
      * Looks up the value of the environment variable.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent (is ignored by this StrLookup).
      * @param key the format to use. If null, the default DateFormat will be used.
      * @return The value of the environment variable.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         return formatDate(event.getTimeMillis(), key);
     }
 
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/EnvironmentLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/EnvironmentLookup.java
index 1d3b811..cf713b9 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/EnvironmentLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/EnvironmentLookup.java
@@ -17,6 +17,7 @@
 package org.apache.logging.log4j.core.lookup;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 
 /**
@@ -27,12 +28,13 @@ public class EnvironmentLookup extends AbstractLookup {
 
     /**
      * Looks up the value of the environment variable.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent (is ignored by this StrLookup).
      * @param key  the key to be looked up, may be null
      * @return The value of the environment variable.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         return System.getenv(key);
     }
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Interpolator.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Interpolator.java
index ec2fbc0..62a69bf 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Interpolator.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Interpolator.java
@@ -22,6 +22,7 @@ import java.util.Map;
 
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.util.PluginManager;
 import org.apache.logging.log4j.core.config.plugins.util.PluginType;
 import org.apache.logging.log4j.core.util.Loader;
@@ -140,7 +141,7 @@ public class Interpolator extends AbstractLookup {
      * resolved
      */
     @Override
-    public String lookup(final LogEvent event, String var) {
+    public String lookup(final Configuration config, final LogEvent event, String var) {
         if (var == null) {
             return null;
         }
@@ -152,7 +153,7 @@ public class Interpolator extends AbstractLookup {
             final StrLookup lookup = lookups.get(prefix);
             String value = null;
             if (lookup != null) {
-                value = event == null ? lookup.lookup(name) : lookup.lookup(event, name);
+                value = event == null ? lookup.lookup(config, name) : lookup.lookup(config, event, name);
             }
 
             if (value != null) {
@@ -161,7 +162,7 @@ public class Interpolator extends AbstractLookup {
             var = var.substring(prefixPos + 1);
         }
         if (defaultLookup != null) {
-            return event == null ? defaultLookup.lookup(var) : defaultLookup.lookup(event, var);
+            return event == null ? defaultLookup.lookup(config, var) : defaultLookup.lookup(config, event, var);
         }
         return null;
     }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JavaLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JavaLookup.java
index 08e3885..3890ddb 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JavaLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JavaLookup.java
@@ -19,6 +19,7 @@ package org.apache.logging.log4j.core.lookup;
 import java.util.Locale;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.util.Strings;
 
@@ -68,7 +69,7 @@ public class JavaLookup extends AbstractLookup {
     }
 
     private String getSystemProperty(final String name) {
-        return spLookup.lookup(name);
+        return spLookup.lookup((Configuration)null, name);
     }
 
     private String getSystemProperty(final String prefix, final String name) {
@@ -91,6 +92,8 @@ public class JavaLookup extends AbstractLookup {
     /**
      * Looks up the value of the environment variable.
      *
+     * @param config
+     *        The Configuration for which the lookup is being attempted
      * @param event
      *        The current LogEvent (is ignored by this StrLookup).
      * @param key
@@ -98,7 +101,7 @@ public class JavaLookup extends AbstractLookup {
      * @return The value of the environment variable.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         switch (key) {
         case "version":
             return "Java version " + getSystemProperty("java.version");
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JndiLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JndiLookup.java
index d7d50cb..1fb8156 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JndiLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/JndiLookup.java
@@ -22,6 +22,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.core.net.JndiManager;
 import org.apache.logging.log4j.status.StatusLogger;
@@ -40,12 +41,13 @@ public class JndiLookup extends AbstractLookup {
 
     /**
      * Looks up the value of the JNDI resource.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent (is ignored by this StrLookup).
      * @param key  the JNDI resource name to be looked up, may be null
      * @return The value of the JNDI resource.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         if (key == null) {
             return null;
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Log4jLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Log4jLookup.java
index 4061900..8577bac 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Log4jLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/Log4jLookup.java
@@ -22,10 +22,9 @@ import java.net.URISyntaxException;
 import java.net.URL;
 
 import org.apache.logging.log4j.core.LogEvent;
-import org.apache.logging.log4j.core.LoggerContext;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.ConfigurationSource;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
-import org.apache.logging.log4j.core.impl.ContextAnchor;
 import org.apache.logging.log4j.status.StatusLogger;
 
 /**
@@ -56,41 +55,43 @@ public class Log4jLookup extends AbstractLookup {
     }
 
     @Override
-    public String lookup(final LogEvent event, final String key) {
-        final LoggerContext ctx = ContextAnchor.THREAD_CONTEXT.get();
-        if (ctx == null) {
-            return null;
-        }
-        final ConfigurationSource configSrc = ctx.getConfiguration().getConfigurationSource();
-        final File file = configSrc.getFile();
-        if (file != null) {
-            switch (key) {
-            case KEY_CONFIG_LOCATION:
-                return file.getAbsolutePath();
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
+        if(config != null) {
+            final ConfigurationSource configSrc = config.getConfigurationSource();
+            final File file = configSrc.getFile();
+            if (file != null) {
+                switch (key) {
+                    case KEY_CONFIG_LOCATION:
+                        return file.getAbsolutePath();
 
-            case KEY_CONFIG_PARENT_LOCATION:
-                return file.getParentFile().getAbsolutePath();
+                    case KEY_CONFIG_PARENT_LOCATION:
+                        return file.getParentFile().getAbsolutePath();
 
-            default:
-                return null;
+                    default:
+                        return null;
+                }
             }
-        }
 
-        final URL url = configSrc.getURL();
-        try {
-            switch (key) {
-            case KEY_CONFIG_LOCATION:
-                return asPath(url.toURI());
+            final URL url = configSrc.getURL();
+            if (url != null) {
+                try {
+                    switch (key) {
+                        case KEY_CONFIG_LOCATION:
+                            return asPath(url.toURI());
 
-            case KEY_CONFIG_PARENT_LOCATION:
-                return asPath(getParent(url.toURI()));
+                        case KEY_CONFIG_PARENT_LOCATION:
+                            return asPath(getParent(url.toURI()));
 
-            default:
-                return null;
+                        default:
+                            return null;
+                    }
+                } catch (final URISyntaxException use) {
+                    LOGGER.error(use);
+                    return null;
+                }
             }
-        } catch (final URISyntaxException use) {
-            LOGGER.error(use);
-            return null;
         }
+
+        return null;
     }
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MainMapLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MainMapLookup.java
index a50de0d..7be9da4 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MainMapLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MainMapLookup.java
@@ -19,6 +19,7 @@ package org.apache.logging.log4j.core.lookup;
 import java.util.Map;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 
 /**
@@ -79,12 +80,12 @@ public class MainMapLookup extends MapLookup {
     }
 
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         return MAIN_SINGLETON.getMap().get(key);
     }
 
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         return MAIN_SINGLETON.getMap().get(key);
     }
 
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MapLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MapLookup.java
index c00645e..675eddb 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MapLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MapLookup.java
@@ -21,6 +21,7 @@ import java.util.List;
 import java.util.Map;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.message.MapMessage;
 
@@ -117,7 +118,7 @@ public class MapLookup implements StrLookup {
     }
 
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         final boolean isMapMessage = event != null && event.getMessage() instanceof MapMessage;
         if (map == null && !isMapMessage) {
             return null;
@@ -140,12 +141,14 @@ public class MapLookup implements StrLookup {
      * If the map is null, then null is returned. The map result object is converted to a string using toString().
      * </p>
      *
+     * @param config
+     *        the Configuration for which the lookup is being attempted
      * @param key
      *        the key to be looked up, may be null
      * @return the matching value, null if no match
      */
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         if (map == null) {
             return null;
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MarkerLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MarkerLookup.java
index 320db49..ccfa275 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MarkerLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/MarkerLookup.java
@@ -20,6 +20,7 @@ package org.apache.logging.log4j.core.lookup;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 
 /**
@@ -33,13 +34,13 @@ public class MarkerLookup extends AbstractLookup {
     static final String MARKER = "marker";
 
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         final Marker marker = event == null ? null : event.getMarker();
         return marker == null ? null : marker.getName();
     }
 
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         return MarkerManager.exists(key) ? key : null;
     }
 
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookup.java
index 83187c2..867c9ae 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookup.java
@@ -23,6 +23,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.status.StatusLogger;
 
@@ -40,6 +41,8 @@ public class ResourceBundleLookup extends AbstractLookup {
      *
      * For example: "com.domain.messages:MyKey".
      *
+     * @param config
+     *        The Configuration for which the lookup is being attempted
      * @param event
      *            The current LogEvent.
      * @param key
@@ -47,7 +50,7 @@ public class ResourceBundleLookup extends AbstractLookup {
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         if (key == null) {
             return null;
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrLookup.java
index e29d280..5378c76 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrLookup.java
@@ -17,6 +17,7 @@
 package org.apache.logging.log4j.core.lookup;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 
 /**
  * Lookup a String key to a String value.
@@ -66,10 +67,11 @@ public interface StrLookup {
      * map.put("number", new Integer(2));
      * assertEquals("2", StrLookup.mapLookup(map).lookup("number"));
      * </pre>
+     * @param config The Configuration for which the lookup is being attempted
      * @param key  the key to be looked up, may be null
      * @return the matching value, null if no match
      */
-    String lookup(String key);
+    String lookup(Configuration config, String key);
 
     /**
      * Looks up a String key to a String value possibly using the current LogEvent.
@@ -94,9 +96,10 @@ public interface StrLookup {
      * map.put("number", new Integer(2));
      * assertEquals("2", StrLookup.mapLookup(map).lookup("number"));
      * </pre>
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent.
      * @param key  the key to be looked up, may be null
      * @return the matching value, null if no match
      */
-    String lookup(LogEvent event, String key);
+    String lookup(Configuration config, LogEvent event, String key);
 }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrSubstitutor.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrSubstitutor.java
index 0b9ead6..1d0d4ba 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrSubstitutor.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StrSubstitutor.java
@@ -25,6 +25,7 @@ import java.util.Map;
 import java.util.Properties;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.util.Strings;
 
 /**
@@ -327,12 +328,13 @@ public class StrSubstitutor {
      * Replaces all the occurrences of variables in the given source object with
      * their matching values from the map.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the source text containing the variables to substitute, null returns null
      * @param valueMap  the map with the values, may be null
      * @return the result of the replace operation
      */
-    public static String replace(final Object source, final Map<String, String> valueMap) {
-        return new StrSubstitutor(valueMap).replace(source);
+    public static String replace(final Configuration config, final Object source, final Map<String, String> valueMap) {
+        return new StrSubstitutor(valueMap).replace(config, source);
     }
 
     /**
@@ -340,6 +342,7 @@ public class StrSubstitutor {
      * their matching values from the map. This method allows to specify a
      * custom variable prefix and suffix
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the source text containing the variables to substitute, null returns null
      * @param valueMap  the map with the values, may be null
      * @param prefix  the prefix of variables, not null
@@ -347,20 +350,21 @@ public class StrSubstitutor {
      * @return the result of the replace operation
      * @throws IllegalArgumentException if the prefix or suffix is null
      */
-    public static String replace(final Object source, final Map<String, String> valueMap, final String prefix,
+    public static String replace(final Configuration config, final Object source, final Map<String, String> valueMap, final String prefix,
                                  final String suffix) {
-        return new StrSubstitutor(valueMap, prefix, suffix).replace(source);
+        return new StrSubstitutor(valueMap, prefix, suffix).replace(config, source);
     }
 
     /**
      * Replaces all the occurrences of variables in the given source object with their matching
      * values from the properties.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source the source text containing the variables to substitute, null returns null
      * @param valueProperties the properties with values, may be null
      * @return the result of the replace operation
      */
-    public static String replace(final Object source, final Properties valueProperties) {
+    public static String replace(final Configuration config, final Object source, final Properties valueProperties) {
         if (valueProperties == null) {
             return source.toString();
         }
@@ -371,7 +375,7 @@ public class StrSubstitutor {
             final String propValue = valueProperties.getProperty(propName);
             valueMap.put(propName, propValue);
         }
-        return StrSubstitutor.replace(source, valueMap);
+        return StrSubstitutor.replace(config, source, valueMap);
     }
 
     //-----------------------------------------------------------------------
@@ -379,27 +383,29 @@ public class StrSubstitutor {
      * Replaces all the occurrences of variables with their matching values
      * from the resolver using the given source string as a template.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the string to replace in, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final String source) {
-        return replace(null, source);
+    public String replace(final Configuration config, final String source) {
+        return replace(null, null, source);
     }
     //-----------------------------------------------------------------------
     /**
      * Replaces all the occurrences of variables with their matching values
      * from the resolver using the given source string as a template.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent if there is one.
      * @param source  the string to replace in, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final String source) {
+    public String replace(final Configuration  config, final LogEvent event, final String source) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(source);
-        if (!substitute(event, buf, 0, source.length())) {
+        if (!substitute(config, event, buf, 0, source.length())) {
             return source;
         }
         return buf.toString();
@@ -413,13 +419,14 @@ public class StrSubstitutor {
      * The rest of the string is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the string to replace in, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final String source, final int offset, final int length) {
-        return replace(null, source, offset, length);
+    public String replace(final Configuration config, final String source, final int offset, final int length) {
+        return replace(config, null, source, offset, length);
     }
 
     /**
@@ -430,18 +437,19 @@ public class StrSubstitutor {
      * The rest of the string is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the string to replace in, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final String source, final int offset, final int length) {
+    public String replace(final Configuration config, final LogEvent event, final String source, final int offset, final int length) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(length).append(source, offset, length);
-        if (!substitute(event, buf, 0, length)) {
+        if (!substitute(config, event, buf, 0, length)) {
             return source.substring(offset, offset + length);
         }
         return buf.toString();
@@ -453,11 +461,12 @@ public class StrSubstitutor {
      * from the resolver using the given source array as a template.
      * The array is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the character array to replace in, not altered, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final char[] source) {
-        return replace(null, source);
+    public String replace(final Configuration config, final char[] source) {
+        return replace(config, null, source);
     }
 
     //-----------------------------------------------------------------------
@@ -466,16 +475,17 @@ public class StrSubstitutor {
      * from the resolver using the given source array as a template.
      * The array is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the character array to replace in, not altered, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final char[] source) {
+    public String replace(final Configuration config, final LogEvent event, final char[] source) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(source.length).append(source);
-        substitute(event, buf, 0, source.length);
+        substitute(config, event, buf, 0, source.length);
         return buf.toString();
     }
 
@@ -488,13 +498,14 @@ public class StrSubstitutor {
      * The rest of the array is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the character array to replace in, not altered, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final char[] source, final int offset, final int length) {
-        return replace(null, source, offset, length);
+    public String replace(final Configuration config, final char[] source, final int offset, final int length) {
+        return replace(config, null, source, offset, length);
     }
 
     /**
@@ -506,18 +517,19 @@ public class StrSubstitutor {
      * The rest of the array is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the character array to replace in, not altered, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final char[] source, final int offset, final int length) {
+    public String replace(final Configuration config, final LogEvent event, final char[] source, final int offset, final int length) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(length).append(source, offset, length);
-        substitute(event, buf, 0, length);
+        substitute(config, event, buf, 0, length);
         return buf.toString();
     }
 
@@ -527,11 +539,12 @@ public class StrSubstitutor {
      * from the resolver using the given source buffer as a template.
      * The buffer is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the buffer to use as a template, not changed, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final StringBuffer source) {
-        return replace(null, source);
+    public String replace(final Configuration config, final StringBuffer source) {
+        return replace(config, null, source);
     }
 
     //-----------------------------------------------------------------------
@@ -540,16 +553,17 @@ public class StrSubstitutor {
      * from the resolver using the given source buffer as a template.
      * The buffer is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the buffer to use as a template, not changed, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final StringBuffer source) {
+    public String replace(final Configuration config, final LogEvent event, final StringBuffer source) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(source.length()).append(source);
-        substitute(event, buf, 0, buf.length());
+        substitute(config, event, buf, 0, buf.length());
         return buf.toString();
     }
 
@@ -562,13 +576,14 @@ public class StrSubstitutor {
      * The rest of the buffer is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the buffer to use as a template, not changed, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final StringBuffer source, final int offset, final int length) {
-        return replace(null, source, offset, length);
+    public String replace(final Configuration config, final StringBuffer source, final int offset, final int length) {
+        return replace(config, null, source, offset, length);
     }
 
     /**
@@ -580,18 +595,19 @@ public class StrSubstitutor {
      * The rest of the buffer is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the buffer to use as a template, not changed, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final StringBuffer source, final int offset, final int length) {
+    public String replace(final Configuration config, final LogEvent event, final StringBuffer source, final int offset, final int length) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(length).append(source, offset, length);
-        substitute(event, buf, 0, length);
+        substitute(config, event, buf, 0, length);
         return buf.toString();
     }
 
@@ -601,11 +617,12 @@ public class StrSubstitutor {
      * from the resolver using the given source builder as a template.
      * The builder is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the builder to use as a template, not changed, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final StringBuilder source) {
-        return replace(null, source);
+    public String replace(final Configuration config, final StringBuilder source) {
+        return replace(config, null, source);
     }
 
     //-----------------------------------------------------------------------
@@ -614,16 +631,17 @@ public class StrSubstitutor {
      * from the resolver using the given source builder as a template.
      * The builder is not altered by this method.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The LogEvent.
      * @param source  the builder to use as a template, not changed, null returns null.
      * @return the result of the replace operation.
      */
-    public String replace(final LogEvent event, final StringBuilder source) {
+    public String replace(final Configuration config, final LogEvent event, final StringBuilder source) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(source.length()).append(source);
-        substitute(event, buf, 0, buf.length());
+        substitute(config, event, buf, 0, buf.length());
         return buf.toString();
     }
     /**
@@ -635,13 +653,14 @@ public class StrSubstitutor {
      * The rest of the builder is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the builder to use as a template, not changed, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final StringBuilder source, final int offset, final int length) {
-        return replace(null, source, offset, length);
+    public String replace(final Configuration config, final StringBuilder source, final int offset, final int length) {
+        return replace(config, null, source, offset, length);
     }
 
     /**
@@ -653,18 +672,19 @@ public class StrSubstitutor {
      * The rest of the builder is not processed, and is not returned.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the builder to use as a template, not changed, null returns null
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the array to be processed, must be valid
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final StringBuilder source, final int offset, final int length) {
+    public String replace(final Configuration config, final LogEvent event, final StringBuilder source, final int offset, final int length) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder(length).append(source, offset, length);
-        substitute(event, buf, 0, length);
+        substitute(config, event, buf, 0, length);
         return buf.toString();
     }
 
@@ -674,11 +694,12 @@ public class StrSubstitutor {
      * their matching values from the resolver. The input source object is
      * converted to a string using <code>toString</code> and is not altered.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the source to replace in, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final Object source) {
-        return replace(null, source);
+    public String replace(final Configuration config, final Object source) {
+        return replace(config, null, source);
     }
     //-----------------------------------------------------------------------
     /**
@@ -686,16 +707,17 @@ public class StrSubstitutor {
      * their matching values from the resolver. The input source object is
      * converted to a string using <code>toString</code> and is not altered.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the source to replace in, null returns null
      * @return the result of the replace operation
      */
-    public String replace(final LogEvent event, final Object source) {
+    public String replace(final Configuration config, final LogEvent event, final Object source) {
         if (source == null) {
             return null;
         }
         final StringBuilder buf = new StringBuilder().append(source);
-        substitute(event, buf, 0, buf.length());
+        substitute(config, event, buf, 0, buf.length());
         return buf.toString();
     }
 
@@ -708,11 +730,11 @@ public class StrSubstitutor {
      * @param source  the buffer to replace in, updated, null returns zero
      * @return true if altered
      */
-    public boolean replaceIn(final StringBuffer source) {
+    public boolean replaceIn(final Configuration config, final StringBuffer source) {
         if (source == null) {
             return false;
         }
-        return replaceIn(source, 0, source.length());
+        return replaceIn(config, source, 0, source.length());
     }
 
     /**
@@ -724,13 +746,14 @@ public class StrSubstitutor {
      * The rest of the buffer is not processed, but it is not deleted.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the buffer to replace in, updated, null returns zero
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the buffer to be processed, must be valid
      * @return true if altered
      */
-    public boolean replaceIn(final StringBuffer source, final int offset, final int length) {
-        return replaceIn(null, source, offset, length);
+    public boolean replaceIn(final Configuration config, final StringBuffer source, final int offset, final int length) {
+        return replaceIn(config, null, source, offset, length);
     }
 
     /**
@@ -742,18 +765,19 @@ public class StrSubstitutor {
      * The rest of the buffer is not processed, but it is not deleted.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the buffer to replace in, updated, null returns zero
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the buffer to be processed, must be valid
      * @return true if altered
      */
-    public boolean replaceIn(final LogEvent event, final StringBuffer source, final int offset, final int length) {
+    public boolean replaceIn(final Configuration config, final LogEvent event, final StringBuffer source, final int offset, final int length) {
         if (source == null) {
             return false;
         }
         final StringBuilder buf = new StringBuilder(length).append(source, offset, length);
-        if (!substitute(event, buf, 0, length)) {
+        if (!substitute(config, event, buf, 0, length)) {
             return false;
         }
         source.replace(offset, offset + length, buf.toString());
@@ -765,11 +789,12 @@ public class StrSubstitutor {
      * Replaces all the occurrences of variables within the given source
      * builder with their matching values from the resolver.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the builder to replace in, updated, null returns zero
      * @return true if altered
      */
-    public boolean replaceIn(final StringBuilder source) {
-        return replaceIn(null, source);
+    public boolean replaceIn(final Configuration config, final StringBuilder source) {
+        return replaceIn(config, null, source);
     }
 
     //-----------------------------------------------------------------------
@@ -777,15 +802,16 @@ public class StrSubstitutor {
      * Replaces all the occurrences of variables within the given source
      * builder with their matching values from the resolver.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event the current LogEvent, if one exists.
      * @param source  the builder to replace in, updated, null returns zero
      * @return true if altered
      */
-    public boolean replaceIn(final LogEvent event, final StringBuilder source) {
+    public boolean replaceIn(final Configuration config, final LogEvent event, final StringBuilder source) {
         if (source == null) {
             return false;
         }
-        return substitute(event, source, 0, source.length());
+        return substitute(config, event, source, 0, source.length());
     }
     /**
      * Replaces all the occurrences of variables within the given source
@@ -795,12 +821,13 @@ public class StrSubstitutor {
      * The rest of the builder is not processed, but it is not deleted.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param source  the builder to replace in, null returns zero
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the builder to be processed, must be valid
      * @return true if altered
      */
-    public boolean replaceIn(final StringBuilder source, final int offset, final int length) {
+    public boolean replaceIn(final Configuration config, final StringBuilder source, final int offset, final int length) {
         return replaceIn(null, source, offset, length);
     }
 
@@ -812,17 +839,18 @@ public class StrSubstitutor {
      * The rest of the builder is not processed, but it is not deleted.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event   the current LogEvent, if one is present.
      * @param source  the builder to replace in, null returns zero
      * @param offset  the start offset within the array, must be valid
      * @param length  the length within the builder to be processed, must be valid
      * @return true if altered
      */
-    public boolean replaceIn(final LogEvent event, final StringBuilder source, final int offset, final int length) {
+    public boolean replaceIn(final Configuration config, final LogEvent event, final StringBuilder source, final int offset, final int length) {
         if (source == null) {
             return false;
         }
-        return substitute(event, source, offset, length);
+        return substitute(config, event, source, offset, length);
     }
 
     //-----------------------------------------------------------------------
@@ -837,14 +865,15 @@ public class StrSubstitutor {
      * the substitution process at the start or end.
      * </p>
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent, if there is one.
      * @param buf  the string builder to substitute into, not null
      * @param offset  the start offset within the builder, must be valid
      * @param length  the length within the builder to be processed, must be valid
      * @return true if altered
      */
-    protected boolean substitute(final LogEvent event, final StringBuilder buf, final int offset, final int length) {
-        return substitute(event, buf, offset, length, null) > 0;
+    protected boolean substitute(final Configuration config, final LogEvent event, final StringBuilder buf, final int offset, final int length) {
+        return substitute(config, event, buf, offset, length, null) > 0;
     }
 
     /**
@@ -852,6 +881,7 @@ public class StrSubstitutor {
      * interpolation method, which resolves the values of all variable references
      * contained in the passed in text.
      *
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent, if there is one.
      * @param buf  the string builder to substitute into, not null
      * @param offset  the start offset within the builder, must be valid
@@ -860,7 +890,7 @@ public class StrSubstitutor {
      * @return the length change that occurs, unless priorVariables is null when the int
      *  represents a boolean flag as to whether any change occurred.
      */
-    private int substitute(final LogEvent event, final StringBuilder buf, final int offset, final int length,
+    private int substitute(final Configuration config, final LogEvent event, final StringBuilder buf, final int offset, final int length,
                            List<String> priorVariables) {
         final StrMatcher prefixMatcher = getVariablePrefixMatcher();
         final StrMatcher suffixMatcher = getVariableSuffixMatcher();
@@ -916,7 +946,7 @@ public class StrSubstitutor {
                                         - startMatchLen);
                                 if (substitutionInVariablesEnabled) {
                                     final StringBuilder bufName = new StringBuilder(varNameExpr);
-                                    substitute(event, bufName, 0, bufName.length());
+                                    substitute(config, event, bufName, 0, bufName.length());
                                     varNameExpr = bufName.toString();
                                 }
                                 pos += endMatchLen;
@@ -954,7 +984,7 @@ public class StrSubstitutor {
                                 priorVariables.add(varName);
 
                                 // resolve the variable
-                                String varValue = resolveVariable(event, varName, buf,
+                                String varValue = resolveVariable(config, event, varName, buf,
                                         startPos, endPos);
                                 if (varValue == null) {
                                     varValue = varDefaultValue;
@@ -964,7 +994,7 @@ public class StrSubstitutor {
                                     final int varLen = varValue.length();
                                     buf.replace(startPos, endPos, varValue);
                                     altered = true;
-                                    int change = substitute(event, buf, startPos,
+                                    int change = substitute(config, event, buf, startPos,
                                             varLen, priorVariables);
                                     change = change
                                             + (varLen - (endPos - startPos));
@@ -1031,13 +1061,13 @@ public class StrSubstitutor {
      * @param endPos  the end position of the variable including the suffix, valid
      * @return the variable's value or <b>null</b> if the variable is unknown
      */
-    protected String resolveVariable(final LogEvent event, final String variableName, final StringBuilder buf,
+    protected String resolveVariable(final Configuration config, final LogEvent event, final String variableName, final StringBuilder buf,
                                      final int startPos, final int endPos) {
         final StrLookup resolver = getVariableResolver();
         if (resolver == null) {
             return null;
         }
-        return resolver.lookup(event, variableName);
+        return resolver.lookup(config, event, variableName);
     }
 
     // Escape
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StructuredDataLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StructuredDataLookup.java
index 379d6a9..6fe7370 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StructuredDataLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/StructuredDataLookup.java
@@ -17,6 +17,7 @@
 package org.apache.logging.log4j.core.lookup;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.message.StructuredDataMessage;
 
@@ -28,22 +29,24 @@ public class StructuredDataLookup implements StrLookup {
 
     /**
      * Returns {@code null}. This Lookup plugin does not make sense outside the context of a LogEvent.
+     * @param config the Configuration for which the lookup is being attempted
      * @param key  the key to be looked up, may be null
      * @return {@code null}
      */
     @Override
-    public String lookup(final String key) {
+    public String lookup(final Configuration config, final String key) {
         return null;
     }
 
     /**
      * Looks up the value for the key using the data in the LogEvent.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent.
      * @param key  the key to be looked up, may be null
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         if (event == null || !(event.getMessage() instanceof StructuredDataMessage)) {
             return null;
         }
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookup.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookup.java
index d2fb530..7c74b68 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookup.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookup.java
@@ -20,6 +20,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.status.StatusLogger;
 
@@ -34,12 +35,13 @@ public class SystemPropertiesLookup extends AbstractLookup {
 
     /**
      * Looks up the value for the key using the data in the LogEvent.
+     * @param config The Configuration for which the lookup is being attempted
      * @param event The current LogEvent.
      * @param key  the key to be looked up, may be null
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         try {
             return System.getProperty(key);
         } catch (final Exception ex) {
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/LiteralPatternConverter.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/LiteralPatternConverter.java
index 0751bca..a38b76c 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/LiteralPatternConverter.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/LiteralPatternConverter.java
@@ -55,7 +55,7 @@ public final class LiteralPatternConverter extends LogEventPatternConverter impl
      */
     @Override
     public void format(final LogEvent event, final StringBuilder toAppendTo) {
-        toAppendTo.append(substitute ? config.getStrSubstitutor().replace(event, literal) : literal);
+        toAppendTo.append(substitute ? config.getStrSubstitutor().replace(config, event, literal) : literal);
     }
     
     /**
@@ -63,7 +63,7 @@ public final class LiteralPatternConverter extends LogEventPatternConverter impl
      */
     @Override
     public void format(final Object obj, final StringBuilder output) {
-        output.append(substitute ? config.getStrSubstitutor().replace(literal) : literal);
+        output.append(substitute ? config.getStrSubstitutor().replace(config, literal) : literal);
     }
 
     /**
@@ -71,7 +71,7 @@ public final class LiteralPatternConverter extends LogEventPatternConverter impl
      */
     @Override
     public void format(final StringBuilder output, final Object... objects) {
-        output.append(substitute ? config.getStrSubstitutor().replace(literal) : literal);
+        output.append(substitute ? config.getStrSubstitutor().replace(config, literal) : literal);
     }
 
     public String getLiteral() {
diff --git a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/MessagePatternConverter.java b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/MessagePatternConverter.java
index 4565e21..1745ccb 100644
--- a/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/MessagePatternConverter.java
+++ b/log4j-core/src/main/java/org/apache/logging/log4j/core/pattern/MessagePatternConverter.java
@@ -70,7 +70,7 @@ public final class MessagePatternConverter extends LogEventPatternConverter {
                     if (toAppendTo.charAt(i) == '$' && toAppendTo.charAt(i + 1) == '{') {
                         final String value = toAppendTo.substring(offset, toAppendTo.length());
                         toAppendTo.setLength(offset);
-                        toAppendTo.append(config.getStrSubstitutor().replace(event, value));
+                        toAppendTo.append(config.getStrSubstitutor().replace(config, event, value));
                     }
                 }
             }
@@ -85,7 +85,7 @@ public final class MessagePatternConverter extends LogEventPatternConverter {
             }
             if (result != null) {
                 toAppendTo.append(config != null && result.contains("${") ?
-                        config.getStrSubstitutor().replace(event, result) : result);
+                        config.getStrSubstitutor().replace(config, event, result) : result);
             } else {
                 toAppendTo.append("null");
             }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ContextMapLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ContextMapLookupTest.java
index b80491e..682d951 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ContextMapLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ContextMapLookupTest.java
@@ -70,9 +70,9 @@ public class ContextMapLookupTest {
     public void testLookup() {
         ThreadContext.put(TESTKEY, TESTVAL);
         final StrLookup lookup = new ContextMapLookup();
-        String value = lookup.lookup(TESTKEY);
+        String value = lookup.lookup(null, TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("BadKey");
+        value = lookup.lookup(null, "BadKey");
         assertNull(value);
     }
 
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/DateLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/DateLookupTest.java
index 09794e2..2626f56 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/DateLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/DateLookupTest.java
@@ -34,7 +34,7 @@ public class DateLookupTest {
     public void testLookup() {
         final StrLookup lookup = new DateLookup();
         final LogEvent event = new MyLogEvent();
-        final String value = lookup.lookup(event, "MM/dd/yyyy");
+        final String value = lookup.lookup(null, event, "MM/dd/yyyy");
         assertNotNull(value);
         assertEquals("12/30/2011", value);
     }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/EnvironmentLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/EnvironmentLookupTest.java
index 5cae1b1..adbcd7b 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/EnvironmentLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/EnvironmentLookupTest.java
@@ -29,9 +29,9 @@ public class EnvironmentLookupTest {
     @Test
     public void testLookup() {
         final StrLookup lookup = new EnvironmentLookup();
-        String value = lookup.lookup("PATH");
+        String value = lookup.lookup(null, "PATH");
         assertNotNull(value);
-        value = lookup.lookup("BadKey");
+        value = lookup.lookup(null, "BadKey");
         assertNull(value);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/InterpolatorTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/InterpolatorTest.java
index 1fcadef..7c036b5 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/InterpolatorTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/InterpolatorTest.java
@@ -72,23 +72,23 @@ public class InterpolatorTest {
         map.put(TESTKEY, TESTVAL);
         final StrLookup lookup = new Interpolator(new MapLookup(map));
         ThreadContext.put(TESTKEY, TESTVAL);
-        String value = lookup.lookup(TESTKEY);
+        String value = lookup.lookup(null, TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("ctx:" + TESTKEY);
+        value = lookup.lookup(null, "ctx:" + TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("sys:" + TESTKEY);
+        value = lookup.lookup(null, "sys:" + TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("BadKey");
+        value = lookup.lookup(null, "BadKey");
         assertNull(value);
         ThreadContext.clearMap();
-        value = lookup.lookup("ctx:" + TESTKEY);
+        value = lookup.lookup(null, "ctx:" + TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("jndi:" + TEST_CONTEXT_RESOURCE_NAME);
+        value = lookup.lookup(null, "jndi:" + TEST_CONTEXT_RESOURCE_NAME);
         assertEquals(TEST_CONTEXT_NAME, value);
     }
 
     private void assertLookupNotEmpty(final StrLookup lookup, final String key) {
-        final String value = lookup.lookup(key);
+        final String value = lookup.lookup(null, key);
         assertNotNull(value);
         assertFalse(value.isEmpty());
         System.out.println(key + " = " + value);
@@ -97,13 +97,13 @@ public class InterpolatorTest {
     @Test
     public void testLookupWithDefaultInterpolator() {
         final StrLookup lookup = new Interpolator();
-        String value = lookup.lookup("sys:" + TESTKEY);
+        String value = lookup.lookup(null, "sys:" + TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("env:PATH");
+        value = lookup.lookup(null, "env:PATH");
         assertNotNull(value);
-        value = lookup.lookup("jndi:" + TEST_CONTEXT_RESOURCE_NAME);
+        value = lookup.lookup(null, "jndi:" + TEST_CONTEXT_RESOURCE_NAME);
         assertEquals(TEST_CONTEXT_NAME, value);
-        value = lookup.lookup("date:yyyy-MM-dd");
+        value = lookup.lookup(null, "date:yyyy-MM-dd");
         assertNotNull("No Date", value);
         final SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
         final String today = format.format(new Date());
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/JndiLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/JndiLookupTest.java
index 97f6a3b..4705bee 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/JndiLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/JndiLookupTest.java
@@ -57,13 +57,13 @@ public class JndiLookupTest {
     public void testLookup() {
         final StrLookup lookup = new JndiLookup();
 
-        String contextName = lookup.lookup(TEST_CONTEXT_RESOURCE_NAME);
+        String contextName = lookup.lookup(null, TEST_CONTEXT_RESOURCE_NAME);
         assertEquals(TEST_CONTEXT_NAME, contextName);
 
-        contextName = lookup.lookup(JndiLookup.CONTAINER_JNDI_RESOURCE_PATH_PREFIX + TEST_CONTEXT_RESOURCE_NAME);
+        contextName = lookup.lookup(null, JndiLookup.CONTAINER_JNDI_RESOURCE_PATH_PREFIX + TEST_CONTEXT_RESOURCE_NAME);
         assertEquals(TEST_CONTEXT_NAME, contextName);
 
-        final String nonExistingResource = lookup.lookup("logging/non-existing-resource");
+        final String nonExistingResource = lookup.lookup(null, "logging/non-existing-resource");
         assertNull(nonExistingResource);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupTest.java
index fc1ca36..014676b 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupTest.java
@@ -43,27 +43,26 @@ public class Log4jLookupTest {
 
     private final static File EXPECT = new File(System.getProperty("user.home"), "/a/b/c/d/e/log4j2.xml");
     private LoggerContext mockCtx = null;
+    private Configuration config = null;
+    private ConfigurationSource configSrc = null;
 
     @Before
     public void setup() throws URISyntaxException {
         this.mockCtx = EasyMock.createMock(LoggerContext.class);
         ContextAnchor.THREAD_CONTEXT.set(mockCtx);
 
-        final Configuration config = EasyMock.createMock(Configuration.class);
-        expect(mockCtx.getConfiguration()).andReturn(config);
+        this.config = EasyMock.createMock(Configuration.class);
         
-        final ConfigurationSource configSrc = EasyMock.createMock(ConfigurationSource.class);
+        this.configSrc = EasyMock.createMock(ConfigurationSource.class);
         expect(config.getConfigurationSource()).andReturn(configSrc);
         expect(configSrc.getFile()).andReturn(EXPECT);
 
-        replay(mockCtx);
-        replay(config);
-        replay(configSrc);
+        replay(mockCtx, config, configSrc);
     }
 
     @After
     public void cleanup() {
-        verify(mockCtx);
+        verify(mockCtx, config, configSrc);
 
         ContextAnchor.THREAD_CONTEXT.set(null);
         this.mockCtx = null;
@@ -72,14 +71,14 @@ public class Log4jLookupTest {
     @Test
     public void lookupConfigLocation() {
         final StrLookup log4jLookup = new Log4jLookup();
-        final String value = log4jLookup.lookup(KEY_CONFIG_LOCATION);
+        final String value = log4jLookup.lookup(config, KEY_CONFIG_LOCATION);
         assertEquals(EXPECT.getAbsolutePath(), value);
     }
 
     @Test
     public void lookupConfigParentLocation() {
         final StrLookup log4jLookup = new Log4jLookup();
-        final String value = log4jLookup.lookup(KEY_CONFIG_PARENT_LOCATION);
+        final String value = log4jLookup.lookup(config, KEY_CONFIG_PARENT_LOCATION);
         assertEquals(EXPECT.getParentFile().getAbsolutePath(), value);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupWithSpacesTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupWithSpacesTest.java
index 3e20159..217cead 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupWithSpacesTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/Log4jLookupWithSpacesTest.java
@@ -41,27 +41,26 @@ public class Log4jLookupWithSpacesTest {
 
     private final static File EXPECT = new File(System.getProperty("user.home"), "/a a/b b/c c/d d/e e/log4j2 file.xml");
     private LoggerContext mockCtx = null;
+    private Configuration config = null;
+    private ConfigurationSource configSrc = null;
 
     @Before
     public void setup() throws URISyntaxException, MalformedURLException {
         this.mockCtx = EasyMock.createMock(LoggerContext.class);
         ContextAnchor.THREAD_CONTEXT.set(mockCtx);
 
-        final Configuration config = EasyMock.createMock(Configuration.class);
-        expect(mockCtx.getConfiguration()).andReturn(config);
+        this.config = EasyMock.createMock(Configuration.class);
 
-        final ConfigurationSource configSrc = EasyMock.createMock(ConfigurationSource.class);
+        this.configSrc = EasyMock.createMock(ConfigurationSource.class);
         expect(config.getConfigurationSource()).andReturn(configSrc);
         expect(configSrc.getFile()).andReturn(EXPECT);
 
-        replay(mockCtx);
-        replay(config);
-        replay(configSrc);
+        replay(mockCtx, config, configSrc);
     }
 
     @After
     public void cleanup() {
-        verify(mockCtx);
+        verify(mockCtx, config, configSrc);
 
         ContextAnchor.THREAD_CONTEXT.set(null);
         this.mockCtx = null;
@@ -70,7 +69,7 @@ public class Log4jLookupWithSpacesTest {
     @Test
     public void lookupConfigLocation_withSpaces() {
         final StrLookup log4jLookup = new Log4jLookup();
-        final String value = log4jLookup.lookup(KEY_CONFIG_LOCATION);
+        final String value = log4jLookup.lookup(config, KEY_CONFIG_LOCATION);
         assertEquals(
                 new File(System.getProperty("user.home"), "/a a/b b/c c/d d/e e/log4j2 file.xml").getAbsolutePath(),
                 value);
@@ -79,7 +78,7 @@ public class Log4jLookupWithSpacesTest {
     @Test
     public void lookupConfigParentLocation_withSpaces() {
         final StrLookup log4jLookup = new Log4jLookup();
-        final String value = log4jLookup.lookup(KEY_CONFIG_PARENT_LOCATION);
+        final String value = log4jLookup.lookup(config, KEY_CONFIG_PARENT_LOCATION);
         assertEquals(new File(System.getProperty("user.home"), "/a a/b b/c c/d d/e e").getAbsolutePath(), value);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MainInputArgumentsJmxLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MainInputArgumentsJmxLookupTest.java
index be1f587..13b9563 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MainInputArgumentsJmxLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MainInputArgumentsJmxLookupTest.java
@@ -36,15 +36,15 @@ public class MainInputArgumentsJmxLookupTest {
     @Test
     public void testMap() {
         final JmxRuntimeInputArgumentsLookup lookup = JmxRuntimeInputArgumentsLookup.JMX_SINGLETON;
-        assertEquals(null, lookup.lookup(null));
-        assertEquals(null, lookup.lookup("X"));
-        assertEquals(null, lookup.lookup("foo.txt"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals(null, lookup.lookup(null, "X"));
+        assertEquals(null, lookup.lookup(null, "foo.txt"));
     }
 
     public void callFromMain() {
         final JmxRuntimeInputArgumentsLookup lookup = JmxRuntimeInputArgumentsLookup.JMX_SINGLETON;
-        assertEquals(null, lookup.lookup(null));
-        assertEquals(null, lookup.lookup("X"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals(null, lookup.lookup(null, "X"));
         // Eclipse adds -Dfile.encoding=Cp1252
         // assertEquals("--file", lookup.lookup("0"));
         // assertEquals("foo.txt", lookup.lookup("1"));
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MapLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MapLookupTest.java
index 313b527..81fe478 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MapLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MapLookupTest.java
@@ -33,8 +33,8 @@ public class MapLookupTest {
     @Test
     public void testEmptyMap() {
         final MapLookup lookup = new MapLookup(new HashMap<String, String>());
-        assertEquals(null, lookup.lookup(null));
-        assertEquals(null, lookup.lookup("X"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals(null, lookup.lookup(null, "X"));
     }
 
     @Test
@@ -42,15 +42,15 @@ public class MapLookupTest {
         final HashMap<String, String> map = new HashMap<>();
         map.put("A", "B");
         final MapLookup lookup = new MapLookup(map);
-        assertEquals(null, lookup.lookup(null));
-        assertEquals("B", lookup.lookup("A"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals("B", lookup.lookup(null, "A"));
     }
 
     @Test
     public void testNullMap() {
         final MapLookup lookup = new MapLookup();
-        assertEquals(null, lookup.lookup(null));
-        assertEquals(null, lookup.lookup("X"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals(null, lookup.lookup(null, "X"));
     }
 
     @Test
@@ -59,12 +59,12 @@ public class MapLookupTest {
                 "--file",
                 "foo.txt" });
         final MapLookup lookup = MainMapLookup.MAIN_SINGLETON;
-        assertEquals(null, lookup.lookup(null));
-        assertEquals(null, lookup.lookup("X"));
-        assertEquals("--file", lookup.lookup("0"));
-        assertEquals("foo.txt", lookup.lookup("1"));
-        assertEquals("foo.txt", lookup.lookup("--file"));
-        assertEquals(null, lookup.lookup("foo.txt"));
+        assertEquals(null, lookup.lookup(null, null));
+        assertEquals(null, lookup.lookup(null, "X"));
+        assertEquals("--file", lookup.lookup(null, "0"));
+        assertEquals("foo.txt", lookup.lookup(null, "1"));
+        assertEquals("foo.txt", lookup.lookup(null, "--file"));
+        assertEquals(null, lookup.lookup(null, "foo.txt"));
     }
 
     @Test
@@ -78,8 +78,8 @@ public class MapLookupTest {
                 .setMessage(message)
                 .build();
       final MapLookup lookup = new MapLookup(map);
-      assertEquals("B", lookup.lookup(event, "A"));
-      assertEquals("B1", lookup.lookup(event, "A1"));
+      assertEquals("B", lookup.lookup(null, event, "A"));
+      assertEquals("B1", lookup.lookup(null, event, "A1"));
     }
 
     @Test
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MarkerLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MarkerLookupTest.java
index d26f895..e2642bf 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MarkerLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/MarkerLookupTest.java
@@ -47,7 +47,7 @@ public class MarkerLookupTest {
                 .setLoggerFqcn("org.apache.logging.log4j.core.Logger") //
                 .setLevel(Level.INFO) //
                 .setMessage(new SimpleMessage("Hello, world!")).build();
-        final String value = strLookup.lookup(event, marker.getName());
+        final String value = strLookup.lookup(null, event, marker.getName());
         assertEquals(markerName, value);
     }
 
@@ -58,7 +58,7 @@ public class MarkerLookupTest {
                 .setLoggerFqcn("org.apache.logging.log4j.core.Logger") //
                 .setLevel(Level.INFO) //
                 .setMessage(new SimpleMessage("Hello, world!")).build();
-        final String value = strLookup.lookup(event, ABSENT_MARKER_NAME);
+        final String value = strLookup.lookup(null, event, ABSENT_MARKER_NAME);
         assertNull(value);
     }
 
@@ -71,7 +71,7 @@ public class MarkerLookupTest {
                 .setLoggerFqcn("org.apache.logging.log4j.core.Logger") //
                 .setLevel(Level.INFO) //
                 .setMessage(new SimpleMessage("Hello, world!")).build();
-        final String value = strLookup.lookup(event, ABSENT_MARKER_NAME);
+        final String value = strLookup.lookup(null, event, ABSENT_MARKER_NAME);
         assertEquals(markerName, value);
     }
 
@@ -83,13 +83,13 @@ public class MarkerLookupTest {
 
     @Test
     public void testLookupExistant() {
-        final String value = strLookup.lookup(MarkerManager.getMarker(markerName).getName());
+        final String value = strLookup.lookup(null, MarkerManager.getMarker(markerName).getName());
         assertEquals(markerName, value);
     }
 
     @Test
     public void testLookupNonExistant() {
-        final String value = strLookup.lookup(ABSENT_MARKER_NAME);
+        final String value = strLookup.lookup(null, ABSENT_MARKER_NAME);
         assertNull(value);
     }
 
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookupTest.java
index 31dcb13..2d0458d 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/ResourceBundleLookupTest.java
@@ -27,25 +27,25 @@ public class ResourceBundleLookupTest {
     @Test
     public void testLookup() {
         final StrLookup lookup = new ResourceBundleLookup();
-        final String value = lookup.lookup("org.apache.logging.log4j.core.lookup.resource-bundle_en:KeyA");
-        Assert.assertEquals("ValueA", lookup.lookup("org.apache.logging.log4j.core.lookup.resource-bundle:KeyA"));
+        final String value = lookup.lookup(null, "org.apache.logging.log4j.core.lookup.resource-bundle_en:KeyA");
+        Assert.assertEquals("ValueA", lookup.lookup(null, "org.apache.logging.log4j.core.lookup.resource-bundle:KeyA"));
     }
 
     @Test
     public void testLookupWithLocale() {
         final StrLookup lookup = new ResourceBundleLookup();
-        final String value = lookup.lookup("org.apache.logging.log4j.core.lookup.resource-bundle:KeyA");
-        Assert.assertEquals("ValueA", lookup.lookup("org.apache.logging.log4j.core.lookup.resource-bundle:KeyA"));
+        final String value = lookup.lookup(null, "org.apache.logging.log4j.core.lookup.resource-bundle:KeyA");
+        Assert.assertEquals("ValueA", lookup.lookup(null, "org.apache.logging.log4j.core.lookup.resource-bundle:KeyA"));
     }
 
     public void testMissingKey() {
         final StrLookup lookup = new ResourceBundleLookup();
-        Assert.assertNull(lookup.lookup("org.apache.logging.log4j.core.lookup.resource-bundle:KeyUnkown"));
+        Assert.assertNull(lookup.lookup(null, "org.apache.logging.log4j.core.lookup.resource-bundle:KeyUnkown"));
     }
 
     @Test
     public void testBadFormatBundleOnly() {
         final StrLookup lookup = new ResourceBundleLookup();
-        Assert.assertNull(lookup.lookup("X"));
+        Assert.assertNull(lookup.lookup(null, "X"));
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StrSubstitutorTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StrSubstitutorTest.java
index a91decb..9e7c3a6 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StrSubstitutorTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StrSubstitutorTest.java
@@ -53,16 +53,16 @@ public class StrSubstitutorTest {
         final StrLookup lookup = new Interpolator(new MapLookup(map));
         final StrSubstitutor subst = new StrSubstitutor(lookup);
         ThreadContext.put(TESTKEY, TESTVAL);
-        String value = subst.replace("${TestKey}-${ctx:TestKey}-${sys:TestKey}");
+        String value = subst.replace(null, "${TestKey}-${ctx:TestKey}-${sys:TestKey}");
         assertEquals("TestValue-TestValue-TestValue", value);
-        value = subst.replace("${BadKey}");
+        value = subst.replace(null, "${BadKey}");
         assertEquals("${BadKey}", value);
 
-        value = subst.replace("${BadKey:-Unknown}-${ctx:BadKey:-Unknown}-${sys:BadKey:-Unknown}");
+        value = subst.replace(null, "${BadKey:-Unknown}-${ctx:BadKey:-Unknown}-${sys:BadKey:-Unknown}");
         assertEquals("Unknown-Unknown-Unknown", value);
-        value = subst.replace("${BadKey:-Unknown}-${ctx:BadKey}-${sys:BadKey:-Unknown}");
+        value = subst.replace(null, "${BadKey:-Unknown}-${ctx:BadKey}-${sys:BadKey:-Unknown}");
         assertEquals("Unknown-${ctx:BadKey}-Unknown", value);
-        value = subst.replace("${BadKey:-Unknown}-${ctx:BadKey:-}-${sys:BadKey:-Unknown}");
+        value = subst.replace(null, "${BadKey:-Unknown}-${ctx:BadKey:-}-${sys:BadKey:-Unknown}");
         assertEquals("Unknown--Unknown", value);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StructuredDataLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StructuredDataLookupTest.java
index 09081dd..bd093c1 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StructuredDataLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/StructuredDataLookupTest.java
@@ -38,9 +38,9 @@ public class StructuredDataLookupTest {
         final Message msg = new StructuredDataMessage("Test", "This is a test", "Audit");
         final LogEvent event = Log4jLogEvent.newBuilder().setLevel(Level.DEBUG).setMessage(msg).build();
         final StrLookup lookup = new StructuredDataLookup();
-        String value = lookup.lookup(event, TESTKEY);
+        String value = lookup.lookup(null, event, TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("BadKey");
+        value = lookup.lookup(null, "BadKey");
         assertNull(value);
     }
 }
diff --git a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookupTest.java b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookupTest.java
index 5749548..3bcdfb8 100644
--- a/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookupTest.java
+++ b/log4j-core/src/test/java/org/apache/logging/log4j/core/lookup/SystemPropertiesLookupTest.java
@@ -43,9 +43,9 @@ public class SystemPropertiesLookupTest {
     @Test
     public void testLookup() {
         final StrLookup lookup = new SystemPropertiesLookup();
-        String value = lookup.lookup(TESTKEY);
+        String value = lookup.lookup(null, TESTKEY);
         assertEquals(TESTVAL, value);
-        value = lookup.lookup("BadKey");
+        value = lookup.lookup(null, "BadKey");
         assertNull(value);
     }
 }
diff --git a/log4j-perf/src/main/java/org/apache/logging/log4j/perf/nogc/NoGcMessagePatternConverter.java b/log4j-perf/src/main/java/org/apache/logging/log4j/perf/nogc/NoGcMessagePatternConverter.java
index 4ecec89..88e3269 100644
--- a/log4j-perf/src/main/java/org/apache/logging/log4j/perf/nogc/NoGcMessagePatternConverter.java
+++ b/log4j-perf/src/main/java/org/apache/logging/log4j/perf/nogc/NoGcMessagePatternConverter.java
@@ -72,7 +72,7 @@ public final class NoGcMessagePatternConverter extends LogEventPatternConverter
             }
             if (result != null) {
                 toAppendTo.append(config != null && result.contains("${") ?
-                        config.getStrSubstitutor().replace(event, result) : result);
+                        config.getStrSubstitutor().replace(config, event, result) : result);
             } else {
                 toAppendTo.append("null");
             }
diff --git a/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/CustomLookup.java b/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/CustomLookup.java
index 471d2ba..a488991 100644
--- a/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/CustomLookup.java
+++ b/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/CustomLookup.java
@@ -20,6 +20,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.core.lookup.AbstractLookup;
 import org.apache.logging.log4j.core.lookup.StrLookup;
@@ -49,7 +50,7 @@ public class CustomLookup extends AbstractLookup {
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         try {
             Map<String, String> properties = loggerProperties.get(event.getLoggerName());
             if (properties == null) {
diff --git a/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/MapMessageLookup.java b/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/MapMessageLookup.java
index 1ed1868..be98010 100644
--- a/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/MapMessageLookup.java
+++ b/log4j-samples/loggerProperties/src/main/java/org/apache/logging/log4j/lookup/MapMessageLookup.java
@@ -20,6 +20,7 @@ import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.Marker;
 import org.apache.logging.log4j.MarkerManager;
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.core.lookup.AbstractLookup;
 import org.apache.logging.log4j.core.lookup.StrLookup;
@@ -50,7 +51,7 @@ public class MapMessageLookup extends AbstractLookup {
      * @return The value associated with the key.
      */
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         Message msg = event.getMessage();
         if (msg instanceof MapMessage) {
             try {
diff --git a/log4j-web/src/main/java/org/apache/logging/log4j/web/Log4jWebInitializerImpl.java b/log4j-web/src/main/java/org/apache/logging/log4j/web/Log4jWebInitializerImpl.java
index 2da549c..113ef70 100644
--- a/log4j-web/src/main/java/org/apache/logging/log4j/web/Log4jWebInitializerImpl.java
+++ b/log4j-web/src/main/java/org/apache/logging/log4j/web/Log4jWebInitializerImpl.java
@@ -96,8 +96,8 @@ final class Log4jWebInitializerImpl extends AbstractLifeCycle implements Log4jWe
         if (this.isInitialized()) {
             super.setStarting();
 
-            this.name = this.substitutor.replace(this.servletContext.getInitParameter(LOG4J_CONTEXT_NAME));
-            final String location = this.substitutor.replace(this.servletContext
+            this.name = this.substitutor.replace(null, this.servletContext.getInitParameter(LOG4J_CONTEXT_NAME));
+            final String location = this.substitutor.replace(null, this.servletContext
                     .getInitParameter(LOG4J_CONFIG_LOCATION));
             final boolean isJndi = "true".equalsIgnoreCase(this.servletContext
                     .getInitParameter(IS_LOG4J_CONTEXT_SELECTOR_NAMED));
diff --git a/log4j-web/src/main/java/org/apache/logging/log4j/web/WebLookup.java b/log4j-web/src/main/java/org/apache/logging/log4j/web/WebLookup.java
index 072f6c9..3cc0e78 100644
--- a/log4j-web/src/main/java/org/apache/logging/log4j/web/WebLookup.java
+++ b/log4j-web/src/main/java/org/apache/logging/log4j/web/WebLookup.java
@@ -21,6 +21,7 @@ package org.apache.logging.log4j.web;
 import javax.servlet.ServletContext;
 
 import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.config.Configuration;
 import org.apache.logging.log4j.core.config.plugins.Plugin;
 import org.apache.logging.log4j.core.lookup.AbstractLookup;
 import org.apache.logging.log4j.util.Strings;
@@ -39,7 +40,7 @@ public class WebLookup extends AbstractLookup {
     }
 
     @Override
-    public String lookup(final LogEvent event, final String key) {
+    public String lookup(final Configuration config, final LogEvent event, final String key) {
         final ServletContext ctx = WebLoggerContextUtils.getServletContext();
         if (ctx == null) {
             return null;
diff --git a/log4j-web/src/test/java/org/apache/logging/log4j/web/WebLookupTest.java b/log4j-web/src/test/java/org/apache/logging/log4j/web/WebLookupTest.java
index a93262e..f641d59 100644
--- a/log4j-web/src/test/java/org/apache/logging/log4j/web/WebLookupTest.java
+++ b/log4j-web/src/test/java/org/apache/logging/log4j/web/WebLookupTest.java
@@ -52,16 +52,16 @@ public class WebLookupTest {
             assertNotNull("No Configuration", config);
             final StrSubstitutor substitutor = config.getStrSubstitutor();
             assertNotNull("No Interpolator", substitutor);
-            String value = substitutor.replace("${web:initParam.TestParam}");
+            String value = substitutor.replace(null, "${web:initParam.TestParam}");
             assertNotNull("No value for TestParam", value);
             assertEquals("Incorrect value for TestParam: " + value, "ParamValue", value);
-            value = substitutor.replace("${web:attr.TestAttr}");
+            value = substitutor.replace(null, "${web:attr.TestAttr}");
             assertNotNull("No value for TestAttr", value);
             assertEquals("Incorrect value for TestAttr: " + value, "AttrValue", value);
-            value = substitutor.replace("${web:Name1}");
+            value = substitutor.replace(null, "${web:Name1}");
             assertNotNull("No value for Name1", value);
             assertEquals("Incorrect value for Name1: " + value, "Ben", value);
-            value = substitutor.replace("${web:Name2}");
+            value = substitutor.replace(null, "${web:Name2}");
             assertNotNull("No value for Name2", value);
             assertEquals("Incorrect value for Name2: " + value, "Jerry", value);
         } catch (final IllegalStateException e) {