Does uo work on macs? I think i can get some friends to play if it does.
http://forums.macnn.com/77/games/222193/any-chance-seeing-ultima-online/ (http://forums.macnn.com/77/games/222193/any-chance-seeing-ultima-online/)
Looks like your mate might have to look into running a Virtual PC. If there's another way, I would imagine that Alder would know it though.
If that mac user is computer savvy at the least, using the instructions for linux should work perfectly.