diff -r 951f34044122 js/src/jsobjinlines.h
--- a/js/src/jsobjinlines.h Tue Feb 15 19:00:55 2011 -0800
+++ b/js/src/jsobjinlines.h Thu Feb 24 21:14:51 2011 +0100
@@ -248,7 +248,7 @@
 inline bool
 JSObject::canHaveMethodBarrier() const
 {
-    return isObject() || isFunction() || isPrimitive() || isDate();
+    return isObject() || isFunction() || isPrimitive() || isDate() || isRegExp();
 }

 inline bool