OK, there is a bit of a readme and the perl script up at...

http://macgeek.dyndns.org/id3_tag/

This will read v1 and v2 tags. Create a new set of tags using that info and directory info if available and write out the updated tags in v1 and v2 format. You should definately make a copy of your files before running this on them just in case. It should "just work" on linux if you follow my directions for using find to call it and start from the top level of your mp3 archive. Let me know how it goes.

-Mike