Suppose the man is blind then. He has the ability to jump but is unaware of the trolley hurliing towards the people on the track. While he has the ability to act his only "crime" is being unaware. Isn't this equivalent to the original trolley problem?

[I]t may rather be supposed that he is the driver of a runaway tram, which he can only steer from one narrow track on to another; five men are working on one track and one man on the other.

In this case, all six men are unaware of the runaway trolley heading towards them, believing themselves to be safe. The one working on his own track has not made up his mind yet as to whether he would want himself to be sacrificed. You would impose your own will onto him, wouldn't you?

I don't have any solution for variations of the trolley problem that satisfy me. I would likely act based upon what I felt was right at the time without considering (all) the implications. Without the threat of running out of time however, I believe it's much more difficult to decide how to act.