### Eclipse Workspace Patch 1.0
#P jackrabbit-core
Index: src/main/java/org/apache/jackrabbit/core/ItemValidator.java
===================================================================
--- src/main/java/org/apache/jackrabbit/core/ItemValidator.java	(revision 984800)
+++ src/main/java/org/apache/jackrabbit/core/ItemValidator.java	(working copy)
@@ -16,18 +16,6 @@
  */
 package org.apache.jackrabbit.core;
 
-import javax.jcr.InvalidItemStateException;
-import javax.jcr.ItemNotFoundException;
-import javax.jcr.NamespaceException;
-import javax.jcr.Node;
-import javax.jcr.Property;
-import javax.jcr.PropertyType;
-import javax.jcr.RepositoryException;
-import javax.jcr.lock.LockException;
-import javax.jcr.nodetype.ConstraintViolationException;
-import javax.jcr.nodetype.ItemDefinition;
-import javax.jcr.version.VersionException;
-
 import org.apache.jackrabbit.core.id.ItemId;
 import org.apache.jackrabbit.core.nodetype.EffectiveNodeType;
 import org.apache.jackrabbit.core.nodetype.NodeTypeConflictException;
@@ -39,12 +27,24 @@
 import org.apache.jackrabbit.core.value.InternalValue;
 import org.apache.jackrabbit.spi.Name;
 import org.apache.jackrabbit.spi.Path;
-import org.apache.jackrabbit.spi.QPropertyDefinition;
 import org.apache.jackrabbit.spi.QItemDefinition;
 import org.apache.jackrabbit.spi.QNodeDefinition;
+import org.apache.jackrabbit.spi.QPropertyDefinition;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import javax.jcr.InvalidItemStateException;
+import javax.jcr.ItemNotFoundException;
+import javax.jcr.NamespaceException;
+import javax.jcr.Node;
+import javax.jcr.Property;
+import javax.jcr.PropertyType;
+import javax.jcr.RepositoryException;
+import javax.jcr.lock.LockException;
+import javax.jcr.nodetype.ConstraintViolationException;
+import javax.jcr.nodetype.ItemDefinition;
+import javax.jcr.version.VersionException;
+
 /**
  * Utility class for validating an item against constraints
  * specified by its definition.
@@ -95,7 +95,7 @@
      * option to check for effective retention policies
      */
     public static final int CHECK_RETENTION = 256;
-    
+
     /**
      * Logger instance for this class
      */
@@ -106,6 +106,8 @@
      */
     protected final SessionContext sessionContext;
 
+    private int enabledChecks = ~0;
+
     /**
      * node type registry
      */
@@ -216,12 +218,24 @@
         EffectiveNodeType.checkSetPropertyValueConstraints(def, values);
     }
 
+    public void enableChecks(int options) {
+        enabledChecks = enabledChecks | options;
+    }
+
+    public void disableChecks(int options) {
+        enabledChecks = enabledChecks & ~options;
+    }
+
+    public int getEnabledChecks() {
+        return enabledChecks;
+    }
+
     public void checkModify(ItemImpl item, int options, int permissions) throws RepositoryException {
-        checkCondition(item, options, permissions, false);
+        checkCondition(item, options & enabledChecks, permissions, false);
     }
 
     public void checkRemove(ItemImpl item, int options, int permissions) throws RepositoryException {
-        checkCondition(item, options, permissions, true);
+        checkCondition(item, options & enabledChecks, permissions, true);
     }
 
     private void checkCondition(ItemImpl item, int options, int permissions, boolean isRemoval) throws RepositoryException {
@@ -275,7 +289,7 @@
     }
 
     public boolean canModify(ItemImpl item, int options, int permissions) throws RepositoryException {
-        return hasCondition(item, options, permissions, false);
+        return hasCondition(item, options & enabledChecks, permissions, false);
     }
 
     private boolean hasCondition(ItemImpl item, int options, int permissions, boolean isRemoval) throws RepositoryException {
@@ -370,7 +384,7 @@
     }
 
 
-    
+
     //-------------------------------------------------< misc. helper methods >
     /**
      * Helper method that builds the effective (i.e. merged and resolved)
@@ -511,4 +525,5 @@
             return id.toString();
         }
     }
+
 }
Index: src/main/java/org/apache/jackrabbit/core/session/SessionState.java
===================================================================
--- src/main/java/org/apache/jackrabbit/core/session/SessionState.java	(revision 984800)
+++ src/main/java/org/apache/jackrabbit/core/session/SessionState.java	(working copy)
@@ -16,14 +16,13 @@
  */
 package org.apache.jackrabbit.core.session;
 
-import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import javax.jcr.RepositoryException;
 import javax.jcr.Session;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import java.util.concurrent.locks.ReentrantLock;
 
 /**
  * Internal session state. This class keeps track of the lifecycle of
@@ -59,7 +58,7 @@
      * synchronization in order to be able to log attempts to concurrently
      * use a session.
      */
-    private final Lock lock = new ReentrantLock();
+    private final ReentrantLock lock = new ReentrantLock();
 
     /**
      * Flag to indicate a closed session. When <code>null</code>, the session
@@ -125,6 +124,29 @@
         }
     }
 
+    public <T> T performUnchecked(SessionOperation<T> operation, int disabledChecks) throws RepositoryException {
+        if (!lock.tryLock()) {
+            log.debug("Attempt to perform {} while another thread is"
+                    + " concurrently accessing the session. Blocking until"
+                    + " the other thread is finished using this session.", operation);
+            lock.lock();
+        }
+        try {
+            checkAlive();
+            log.debug("Performing {}", operation);
+            if (lock.getHoldCount() == 1) {
+                context.getItemValidator().disableChecks(disabledChecks);
+            }
+            return operation.perform(context);
+        }
+        finally {
+            if (lock.getHoldCount() == 1) {
+                context.getItemValidator().enableChecks(disabledChecks);
+            }
+            lock.unlock();
+        }
+    }
+
     /**
      * Closes this session.
      *