What type of jumping are you wanting to do...and at what level?
He would not be my first choice when I think "jumper". When I look at him, I think "ranch pony" regardless of what his movement is like.
Given the proper training, he could probably do okay at lower levels...but pretty much any horse can. If you are looking for something at higher levels, then I would want to look at horses that had been trained to jump...and had video/pictures so that I could see them jump.
I wouldn't want to spend money to take a risk on "he's cute, maybe he can jump".