I think Aceofone answered it pretty well.
If you are almost certain you are up against a pocket pair, no matter which pocket pair, you've got to fold your AK at this point in the tourney.

If you are fairly certain the guy does not have a PP and think maybe he is trying to steal, AK is a decent hand to call with, provided your stack covers him.

The biggest thing to keep in mind is that by shoving all of your chips in when you are on the verge of placing in the money, you are taking a big gamble on your entire buy-in, plus the opportunity cost of what you would be missing if you placed deep in the money.