Eh?

One doesn't expect much of the players at $25NL, but tonight, between bouts of packing, something happened, which left me scratching my head even at this level.

Three limpers to me on the button with A♠J♦. I just limp too. Flop is A♣8♦4♥. There are not many hands that I'm worried about, just A4, A8, 88 and 44. When everyone checks to me I bet the pot hoping to drag along a weak ace and avoid his kicker. Everyone folds except the last of the limpers who makes baby Jebus cry with a check min-raise. He's shown distinct maniacal tendencies in the time I've been here, so I'm not too worried. Nevertheless, I simply call.

The turn is the glorious J♠. He checks, I bet $4 into the $7.50 pot. Baby Jebus cries again, when he once again check min-raises to $8. I reraise to $16 which coincidentally is exactly enough to put him all in. He calls, and I resign myself to a split pot (or a loss to 88 or 44). The Q♦ on the river adds another bit of worry, until he turns over K♣6♥.

Eh?

Even if he thought the check min-raises were a clever way of pretending to be strong, what on earth is going on with the final call?