--- a/addon-sdk/source/lib/sdk/loader/cuddlefish.js
+++ b/addon-sdk/source/lib/sdk/loader/cuddlefish.js
@@ -21,17 +21,17 @@ const { classes: Cc, Constructor: CC, in
 // `loadSandbox` is exposed by bootstrap.js
 const loaderURI = module.uri.replace("sdk/loader/cuddlefish.js",
                                      "toolkit/loader.js");
 const xulappURI = module.uri.replace("loader/cuddlefish.js",
                                      "system/xul-app.jsm");
 // We need to keep a reference to the sandbox in order to unload it in
 // bootstrap.js
 
-const loaderSandbox = loadSandbox(loaderURI);
+var loaderSandbox = loadSandbox(loaderURI);
 const loaderModule = loaderSandbox.exports;
 
 const { incompatibility } = Cu.import(xulappURI, {}).XulApp;
 
 const { override, load } = loaderModule;
 
 function CuddlefishLoader(options) {
   let { manifest } = options;