Index: test/java/org/apache/ivy/util/IvyPatternHelperTest.java
===================================================================
--- test/java/org/apache/ivy/util/IvyPatternHelperTest.java	(revision 806404)
+++ test/java/org/apache/ivy/util/IvyPatternHelperTest.java	(working copy)
@@ -17,6 +17,7 @@
  */
 package org.apache.ivy.util;
 
+import java.lang.reflect.Field;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -69,4 +70,21 @@
             pattern, "apache", "Test", "1.0", "test", "jar", "jar"));
     }
 
+    public void testWindowsCompatibleFilenames() throws Exception {
+        String pattern = "[organization]/[module]/special:chars/[type]/[artifact].[version].[ext]";
+        String org = "org.example?", module = "test|", version = "\"8.3\"", artifact = "ba*se", type = "<jar>", ext = "wh/y"; 
+        setWindowsPlatform(true);
+        assertEquals("org.example_/test_/special_chars/_jar_/ba_se._8.3_.wh_y",
+                IvyPatternHelper.substitute(pattern, org, module, version, artifact, type, ext));
+
+        setWindowsPlatform(false);
+        assertEquals("org.example?/test|/special:chars/<jar>/ba*se.\"8.3\".wh/y",
+            IvyPatternHelper.substitute(pattern, org, module, version, artifact, type, ext));
+    }
+
+    private void setWindowsPlatform(boolean b) throws Exception {
+        Field f = IvyPatternHelper.class.getDeclaredField("windowsPlatform");
+        f.setAccessible(true);
+        f.setBoolean(null, b);
+    }
 }
Index: src/java/org/apache/ivy/core/IvyPatternHelper.java
===================================================================
--- src/java/org/apache/ivy/core/IvyPatternHelper.java	(revision 806404)
+++ src/java/org/apache/ivy/core/IvyPatternHelper.java	(working copy)
@@ -34,6 +34,7 @@
 import org.apache.ivy.core.settings.IvyVariableContainer;
 import org.apache.ivy.core.settings.IvyVariableContainerImpl;
 import org.apache.ivy.util.Message;
+import org.apache.ivy.util.StringUtils;
 
 /**
  */
@@ -67,6 +68,21 @@
 
     private static final Pattern VAR_PATTERN = Pattern.compile("\\$\\{(.*?)\\}");
 
+    private static final char[] WINDOWS_INVALID_FILENAME_CHARS = {'[', ']', '<', '>', ':', '|', '\"'};
+
+    private static final char[] SLASHES = {'\\', '/'};
+
+
+    private static boolean windowsPlatform;
+    static {
+        try {
+            windowsPlatform = System.getProperty("os.name").indexOf("windows") > -1;
+        } catch (SecurityException ignored) {
+            //don't fail when running under a restrictive security manager
+            windowsPlatform = false;
+        }
+    }
+
     public static String substitute(String pattern, ModuleRevisionId moduleRevision) {
         return substitute(pattern, moduleRevision.getOrganisation(), moduleRevision.getName(),
             moduleRevision.getBranch(), moduleRevision.getRevision(), "ivy", "ivy", "xml", null,
@@ -268,8 +284,7 @@
                     }
 
                     String token = tokenBuffer.toString();
-                    Object tokenValue = tokensCopy.get(token);
-                    String value = (tokenValue == null) ? null : tokenValue.toString();
+                    String value = scrub(tokensCopy.get(token), EXT_KEY.equals(token));
 
                     if (insideOptionalPart) {
                         tokenHadValue = (value != null) && (value.length() > 0);
@@ -494,4 +509,19 @@
         }
         return pattern.substring(startIndex + 1, endIndex);
     }
+
+    private static String scrub(Object value, boolean removeSlashes) {
+        if (value == null) {
+            return null;
+        }
+        if (!windowsPlatform) {
+            return value.toString();
+        }
+        final char substitute = '_';
+        String s = StringUtils.replaceChars(value.toString(), WINDOWS_INVALID_FILENAME_CHARS, substitute);
+        if (removeSlashes) {
+            s = StringUtils.replaceChars(s, SLASHES, substitute);
+        }
+        return s;
+    }
 }
Index: src/java/org/apache/ivy/util/StringUtils.java
===================================================================
--- src/java/org/apache/ivy/util/StringUtils.java	(revision 806404)
+++ src/java/org/apache/ivy/util/StringUtils.java	(working copy)
@@ -189,4 +189,18 @@
         return sb.toString();
     }
 
+    public static String replaceChars(String s, char[] removeChars, char replacement) {
+        if (s == null || removeChars == null) {
+            return s;
+        }
+        char[] cs = s.toCharArray();
+        for (int i=0; i < removeChars.length; i++) {
+            for (int j=0; j < cs.length; j++) {
+                if (cs[j] == removeChars[i]) {
+                    cs[j] = replacement;
+                }
+            }
+        }
+        return new String(cs);
+    }
 }