Has anyone ever tried to use "require.ensure' in this project?

I've tried to get this (https://github.com/reactjs/react-router/issues/3232 ) to work, but without success. I ran into the following problems.
- require.ensuire is not a function.
- After I polly-fill the require.ensure for the server-side, the project builds and runs but the routes are not working.
- Due to the second problem above, I checked the webpack package using the tool at http://webpack.github.io/analyse/#home where I found that webpack never created the split point chunk.

One curious thing though, when I used the AMD version of require (require([], cb) instead of require.ensure([], cb)), webpack did generated the chunk for the split point. But the routes still didn't work.

Any thoughts?