diff --git a/mozilla/js/rhino/src/org/mozilla/javascript/optimizer/Codegen.java b/mozilla/js/rhino/src/org/mozilla/javascript/optimizer/Codegen.java
index 352be18e9fd..1a71fc552f7 100644
--- a/mozilla/js/rhino/src/org/mozilla/javascript/optimizer/Codegen.java
+++ b/mozilla/js/rhino/src/org/mozilla/javascript/optimizer/Codegen.java
@@ -80,6 +80,7 @@ public class Codegen extends Interpreter {
         Exception e = null;
         Class result = null;
         DefiningClassLoader classLoader = new DefiningClassLoader();
+        nameHelper.reset();
 
         try {
             if (cx.getOptimizationLevel() > 0) {