--- a/addon-sdk/source/lib/sdk/loader/sandbox.js
+++ b/addon-sdk/source/lib/sdk/loader/sandbox.js
@@ -58,17 +58,19 @@ exports.evaluate = evaluate;
  *    It must be a local chrome:, resource:, file: or data: URL.
  */
 function load(sandbox, uri) {
   if (uri.indexOf('data:') === 0) {
     let source = uri.substr(uri.indexOf(',') + 1);
 
     return evaluate(sandbox, decodeURIComponent(source), '1.8', uri, 0);
   } else {
-    return scriptLoader.loadSubScript(uri, sandbox, 'UTF-8');
+    return scriptLoader.loadSubScriptWithOptions(uri, {target: sandbox,
+                                                       charset: 'UTF-8',
+                                                       wantReturnValue: true});
   }
 }
 exports.load = load;
 
 /**
  * Forces the given `sandbox` to be freed immediately.
  */
 exports.nuke = Cu.nukeSandbox