--- old/src/share/vm/services/memSnapshot.cpp	2012-12-17 16:19:25.923400500 +0100
+++ new/src/share/vm/services/memSnapshot.cpp	2012-12-17 16:19:25.627000000 +0100
@@ -389,7 +389,11 @@
 MemSnapshot::~MemSnapshot() {
   assert(MemTracker::shutdown_in_progress(), "native memory tracking still on");
   {
-    MutexLockerEx locker(_lock);
+    MonitorLockerEx locker(_lock);
+
+    // wakeup all waiters
+    locker.notify_all();
+
     if (_alloc_ptrs != NULL) {
       delete _alloc_ptrs;
       _alloc_ptrs = NULL;