diff -r be6959017765 -r 4c471254865e hotspot/src/share/vm/runtime/thread.cpp
--- a/hotspot/src/share/vm/runtime/thread.cpp	Wed Oct 07 19:01:55 2009 -0400
+++ b/hotspot/src/share/vm/runtime/thread.cpp	Fri Oct 16 02:05:46 2009 -0700
@@ -1213,6 +1213,7 @@
 {
   initialize();
   _is_attaching = is_attaching;
+  assert(_deferred_card_mark.is_empty(), "Default MemRegion ctor");
 }
 
 bool JavaThread::reguard_stack(address cur_sp) {
@@ -2318,6 +2319,10 @@
 
 
 void JavaThread::oops_do(OopClosure* f, CodeBlobClosure* cf) {
+  // Flush deferred store-barriers, if any, associated with
+  // initializing stores done by this JavaThread in the current epoch.
+  Universe::heap()->flush_deferred_store_barrier(this);
+
   // The ThreadProfiler oops_do is done from FlatProfiler::oops_do
   // since there may be more than one thread using each ThreadProfiler.