diff -r a78533d1bbc6 -r f51518b30c84 jdk/src/share/classes/sun/misc/VM.java
--- a/jdk/src/share/classes/sun/misc/VM.java	Fri Oct 21 18:01:01 2011 +0900
+++ b/jdk/src/share/classes/sun/misc/VM.java	Mon Oct 24 20:55:08 2011 +0100
@@ -371,6 +371,12 @@
     private final static int JVMTI_THREAD_STATE_WAITING_INDEFINITELY = 0x0010;
     private final static int JVMTI_THREAD_STATE_WAITING_WITH_TIMEOUT = 0x0020;
 
+    /*
+     * Returns the first non-null class loader up the execution stack,
+     * or null if only code from the null class loader is on the stack.
+     */
+    public static native ClassLoader latestUserDefinedLoader();
+
     static {
         initialize();
     }