--- a/jdk/src/share/classes/java/util/RegularEnumSet.java	Mon Mar 14 11:45:21 2011 -0700
+++ b/jdk/src/share/classes/java/util/RegularEnumSet.java	Mon Mar 14 14:49:52 2011 -0700
@@ -106,7 +106,7 @@
         public void remove() {
             if (lastReturned == 0)
                 throw new IllegalStateException();
-            elements -= lastReturned;
+            elements &= ~lastReturned;
             lastReturned = 0;
         }
     }