M2M, this spot and ones like it are one of the problems I cause myself a lot. I don't even mind the preflop hand choice, as I think he's folding to this 4b 80% of the time or more. Now, you've got 5 outs to beat whatever hands he has that beat you, and some fold equity. I like meeloche's line.

Of course, I've been away from poker for 5 months, so big grain of salt imo.