his move isn't out of line now.
Result
http://twodimes.net/h/?z=1400387
pokenum -h ac as - jd 9d -- kd qh 6d
Holdem Hi: 990 enumerated boards containing Kd 6d Qh
cards win %win lose %lose tie %tie EV
As Ac 535 54.04 455 45.96 0 0.00 0.540
Jd 9d 455 45.96 535 54.04 0 0.00 0.460
If he thinks there is any chance that you'll fold, and you must have considered it on that flop, then his move is basically a coinflip that he won this time. Moves like this are great because next time he tries this same move he might have 66 and you'll think he's drawing again and get your money in dead....see why it's good poker?