Index: VERSION.txt
===================================================================
--- VERSION.txt	(revision 6077)
+++ VERSION.txt	(working copy)
@@ -2,6 +2,7 @@
  + Jetty-6 is now in maintenance mode.
  + JETTY-1212 Long content lengths
  + JETTY-1214 Avoid ISE when scavenging invalid session
+ + JETTY-1226 javax.activation needs to be listed in the system classes
  + JETTY-1237 Remember local/remote details of endpoint
  + COMETD-112 if two threads create the same channel, then create events may occur after subscribe events
 
Index: modules/jetty/src/main/java/org/mortbay/jetty/webapp/WebAppContext.java
===================================================================
--- modules/jetty/src/main/java/org/mortbay/jetty/webapp/WebAppContext.java	(revision 6077)
+++ modules/jetty/src/main/java/org/mortbay/jetty/webapp/WebAppContext.java	(working copy)
@@ -94,8 +94,30 @@
     private boolean _logUrlOnStart =false;
     private boolean _parentLoaderPriority= Boolean.getBoolean("org.mortbay.jetty.webapp.parentLoaderPriority");
     private PermissionCollection _permissions;
-    private String[] _systemClasses = {"java.","javax.servlet.","javax.xml.","org.mortbay.","org.xml.","org.w3c.", "org.apache.commons.logging.", "org.apache.log4j."};
-    private String[] _serverClasses = {"-org.mortbay.jetty.plus.jaas.", "org.mortbay.jetty.", "org.slf4j."}; // TODO hide all mortbay classes
+    private String[] _systemClasses =
+    {
+        "java.",                            // Java SE classes (per servlet spec v2.5 / SRV.9.7.2) 
+        "javax.",                           // Java SE classes (per servlet spec v2.5 / SRV.9.7.2)
+        "org.xml.",                         // needed by javax.xml
+        "org.w3c.",                         // needed by javax.xml
+        "org.apache.commons.logging.",      // special case 
+        "org.apache.log4j.",                // special case
+        "org.mortbay.cometd.continuation.",   // cannot change
+        "org.mortbay.jetty.plus.annotation.", // cannot change
+        "org.mortbay.jetty.plus.jaas.",       // cannot change
+        "org.mortbay.jetty.plus.naming.",     // cannot change
+        "org.mortbay.jetty.servlet.DefaultServlet" // cannot change
+    };
+    private String[] _serverClasses = 
+    {
+        "-org.mortbay.cometd.continuation.",    // don't hide
+        "-org.mortbay.jetty.plus.annotation.", // don't hide
+        "-org.mortbay.jetty.plus.jaas.",       // don't hide 
+        "-org.mortbay.jetty.plus.naming.",     // don't hide
+        "-org.mortbay.jetty.servlet.DefaultServlet", // don't hide
+        "org.slf4j.",                          // special case
+        "org.mortbay."                         // hide jetty classes
+    };
     private File _tmpDir;
     private boolean _isExistingTmpDir;
     private String _war;