Not sure exactly what triggers this, but I had it happen in several different situations - each time, it was equipping a new weapon on my heroes, and the game promptly crashed. I don't have the windows error log, but here's the save file in question, I had it happen three times, so it should be reproducable.

[URL=http://depositfiles.com/files/f6go13zir]http://depositfiles.com/files/f6go13zir[/URL]

edit: Seems to be related to trade and equip or equip while swapping a weapon already equipped? I was able to equip a new weapon by using trade, unequip, equip without incident