Any sequencer worthy of it's name can do that job easily. Cubase, Logic, Sonar, you name it.

You gotta understand, there are two types of midi.
Midi Type 0 have all the info in one part, midi type 1 have all channels in different parts. The sequencers mentioned all have a function to disolve type 0 files into type 1 (and usually you'll find it with that name "disolve").