I was getting some last minute practice in before a league match tomorrow when this board cropped up. As far as I could tell, in the 16 times it was played in the main bridge club, no two auctions were the same. What would your auction be here? The auction posted was what happened at my table for what it's worth.
edit: It's also a pretty cool play/defend problem if East were allowed to play 4S (at least if you don't click the GIB button).