sucks when that happens...but having AA does not mean you have a 100% chance to win unfortunately...just sucks when your part of the 10% or whatever it is that isn't the 90% favored to win
when i've cracked AA with AK...its usually with a straight or a flush..your situation is pretty unique, although there was a time where I had pocket 10's to a guy's pocket kings...with a king on the flop...followed by 10/10 on the turn and river...thought that was cool...but a pretty bad beat for the other guy