I recently discovered (pretty much by accident) that iTunes and the iPhone supports multiple audio tracks in a single m4v video file. So I've started ripping my DVDs using Handbrake with both the main audio and the commentary track.

In iTunes and my iPhone I can swop between the two at will, but I cannot find any information on how or if it's possible to switch audio tracks on the AppleTV. Does anybody know?

Is it the sort of thing that could be hacked to work?