Oh, nothing was wrong with him (other than the kitten insanity that all of them have): I'm out of town for the holiday season, and he is boarding with them. I called them up yesterday and got "Is there a thing as too much petting for that cat?" To which I deadpanned "Heck no." They laughed at that. Apparently he's been sticking his paw out of the kennel as someone walks by and fwapping them so they stop and pay attention to him.

My cat is a sneaky ninja.