Just kidding. I ran the road and mountain versions (short cage vs. long cage) with Grip Shift X-Rays and Deore thumbies and both worked great. Just make sure your largest cog isn't over 28 teeth if your using the road version.
As already noted, Sachs New Success mtb derailleurs work beautifully with shimano shifters.
However, I think I remember reading somewhere that the road shifters pull an amount of cable somewhere between the amount of ultegra and campy, so the road derailleur may not work with shimano mtb shifters. Haven't tried it though, so I can't say for sure.