Someone else hopefully has an easier (er, 'real') answer...
But, you might try this, since you have XP machines available:
I've been playing with the 30 day trial of a font editor to clean up some of the things in MrHand (a copyrighted font - so I can't distribute it of course) that I don't like and make it more readable to my eye...
http://www.high-logic.com/download.html
Open your font in FontCreator 5.5 and go to the Format | Naming menu/dialog. You'll probably see Macintosh Roman under Platform - as well as one ore more Unicode entries (for XP). Compare the font family name used for Macintosh vs Unicode... that might be where the 55 is screwed up. Make the names identical for each platform, save the font as a new name (e.g., Name-Your Firm). Uninstall the old font on each machine (Font control panel on XP, drag to trash from Fonts folder on Mac) and install your revised copy.
Cheers,
Karl
PS Something I learned from reading the manual for the above is that the name of the font file has nothing to do with the name of the font as installed! Only the contents of the Naming block are used on each platform. The file can have any name... so the folder/names that you see in Finder / Explorer are meaningless to solving the problem.
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