diff --git a/js/src/xpconnect/src/xpcconvert.cpp b/js/src/xpconnect/src/xpcconvert.cpp
index 882ce67e90ee..d1545d2aef0f 100644
--- a/js/src/xpconnect/src/xpcconvert.cpp
+++ b/js/src/xpconnect/src/xpcconvert.cpp
@@ -291,6 +291,8 @@ XPCConvert::NativeData2JS(XPCLazyCallContext& lccx, jsval* d, const void* s,
     case nsXPTType::T_JSVAL :
         JS_STATIC_ASSERT(sizeof(jsval) <= sizeof(uint64));
         *d = **((jsval**)s);
+        if (!JS_WrapValue(cx, d))
+            return JS_FALSE;
         break;
 
     default: