Comment 7 for bug 1169244

It's probably best to perform a reverse kernel bisect to figure which commit fixes this issue.

One question, does this issue only happen after undocking then trying to use ethernet? Does it happen if you perform a cold boot without using the dock?

Also, can you test the latest upstream 3.8 stable kernel, just to confirm it's not fixed there yet:
http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.8.8-raring/