PR for the issue69 branch. It now fails.

This is related to issue #69 

The problem seems to be a misplaced `'use strict';` expression, as shown in the sockjs_handler.js file. My intention was to have it in the start of my function.

It only causes problems when building with assetgraph-builder, and as mentioned, it could be solved by adding a var statement in the sockjs.js file.

Hope this helps.