--- a/hotspot/src/cpu/x86/vm/stubGenerator_x86_64.cpp	Tue Mar 24 15:09:52 2009 -0700
+++ b/hotspot/src/cpu/x86/vm/stubGenerator_x86_64.cpp	Thu Mar 26 14:31:45 2009 -0700
@@ -637,7 +637,7 @@
   address generate_orderaccess_fence() {
     StubCodeMark mark(this, "StubRoutines", "orderaccess_fence");
     address start = __ pc();
-    __ mfence();
+    __ membar(Assembler::StoreLoad);
     __ ret(0);
 
     return start;