If you listen to Korean/Chinese/Japanese music through iTunes, but get scrambles instead of the correct unicode set, this may help. This is not a solution for everyone since it requires the Windows version of iTunes, but it's a good way to fix the problem for those of you that do.
I've been using my iBook for music now for over a year now, but most of my music will not be encoded correctly by iTunes. However, if I first load the songs in iTunes for Windows, then I right-click the song (or multiple songs) then convert ID3 tag version to 2.4, it seems to work perfectly when I transfer them back to the Mac.
Also, you can do this through a network (leaving all the songs in your Mac's iTunes playlists) by adding the songs if you don't want to move the songs to your PC (it'll take a bit longer). Then when iTunes on the Mac refreshes the songs, the new tags will show up.
Important: make sure the iTunes on your PC isn't copying files to its own music library by checking the prefs.
My friends use this too, and it seems to work great. Hope this helps others with mis-encoded tags. Or that Apple will fix this bug?
Mac OS X Hints
http://hints.macworld.com/article.php?story=20040221170458983