Preflop spot in Main Event

[T_Mac]

This seemed like a real close spot. Villain in this hand is Riverboatking, HSNL cash player. Earlier he had been playing a lot more aggressively preflop raising and squeezing a lot but seemed to have calmed down a bit lately. He's lost a few pots to bad luck, and bluffed some off and never been able to chip up. Blinds are 200/400 with a 50 ante. So 1100 in the pot preflop. RBK has about 11k and had just pushed the hand or 2 hands earlier to win the blinds. But again he had been pretty quiet before that. Pretty much everyone on my left is a nit, and RBK is two to my right. Oh one player to my right is basically invisible, hes played 2 hands in a billion hours so he doesn't count. This hand RBK pushes again for 11k or so after 3 or 4 folds and I look down at AJ of spades on the button or cutoff. I don't remember exactly how many chips I had, over 50k, maybe 70k, enough so losing 11k wouldn't hurt me much at all. But I don't want to double RBK up, and 11 or 12k is a lot to call with AJ...also any validity to the idea that the 2nd time he does it hes more likely to have a real hand? Cuz that thought crossed my mind...anyway call or fold?