No recalls that I'm aware of...though some hoses were replaced on request at one time, seems like they had some bad fittings if I remember right.
You are the first one I've heard of with a leak in the gearbox of the MMM. You sure it wasn't overfilled? In any case, I'll bet it's an easy seal replacement...
Good luck and if you replace the seal, make sure you take some pics and post it as a project....I doubt you'll be the only one ever to replace it....