diff --git a/mozilla/js2/src/js2metadata.cpp b/mozilla/js2/src/js2metadata.cpp
index 184e6b72ca0..2170ea2874e 100644
--- a/mozilla/js2/src/js2metadata.cpp
+++ b/mozilla/js2/src/js2metadata.cpp
@@ -3132,7 +3132,7 @@ static const uint8 urlCharType[256] =
         SimpleInstance *fInst = new SimpleInstance(functionClass);
         fInst->fWrap = new FunctionWrapper(true, new ParameterFrame(JS2VAL_VOID, true), code);
         writeDynamicProperty(glob, new Multiname(&world.identifiers[name], publicNamespace), true, OBJECT_TO_JS2VAL(fInst), RunPhase);
-        writeDynamicProperty(fInst, new Multiname(engine->length_StringAtom, publicNamespace), true, length, RunPhase);
+        writeDynamicProperty(fInst, new Multiname(engine->length_StringAtom, publicNamespace), true, INT_TO_JS2VAL(length), RunPhase);
     }
 
 #define MAKEBUILTINCLASS(c, super, dynamic, allowNull, final, name, defaultVal) c = new JS2Class(super, NULL, new Namespace(engine->private_StringAtom), dynamic, allowNull, final, name); c->complete = true; c->defaultValue = defaultVal;