diff --git a/js/jetpack/JetpackChild.cpp b/js/jetpack/JetpackChild.cpp
index ffc6a7b6e09e..32218a7134d3 100644
--- a/js/jetpack/JetpackChild.cpp
+++ b/js/jetpack/JetpackChild.cpp
@@ -111,7 +111,7 @@ JetpackChild::Init(base::ProcessHandle aParentProcessHandle,
     JSAutoRequest request(mCx);
     JS_SetContextPrivate(mCx, this);
     JSObject* implGlobal =
-      JS_NewGlobalObject(mCx, const_cast<JSClass*>(&sGlobalClass));
+      JS_NewCompartmentAndGlobalObject(mCx, const_cast<JSClass*>(&sGlobalClass), NULL);
     if (!implGlobal ||
         !JS_InitStandardClasses(mCx, implGlobal) ||
         !JS_DefineFunctions(mCx, implGlobal,
@@ -396,10 +396,14 @@ JetpackChild::CreateSandbox(JSContext* cx, uintN argc, jsval* vp)
     return JS_FALSE;
   }
 
-  JSObject* obj = JS_NewGlobalObject(cx, const_cast<JSClass*>(&sGlobalClass));
+  JSObject* obj = JS_NewCompartmentAndGlobalObject(cx, const_cast<JSClass*>(&sGlobalClass), NULL);
   if (!obj)
     return JS_FALSE;
 
+  JSAutoCrossCompartmentCall ac;
+  if (!ac.enter(cx, obj))
+    return JS_FALSE;
+
   JS_SET_RVAL(cx, vp, OBJECT_TO_JSVAL(obj));
   return JS_InitStandardClasses(cx, obj);
 }
@@ -427,6 +431,10 @@ JetpackChild::EvalInSandbox(JSContext* cx, uintN argc, jsval* vp)
   if (!str)
     return JS_FALSE;
 
+  JSAutoCrossCompartmentCall ac;
+  if (!ac.enter(cx, obj))
+    return JS_FALSE;
+
   js::AutoValueRooter ignored(cx);
   return JS_EvaluateUCScript(cx, obj, JS_GetStringChars(str), JS_GetStringLength(str), "", 1,
                              ignored.jsval_addr());