OSX's Unicode support allows for various languages to be used in the system. The Finder is able to display international languages with no problems. However, viewing files with non-English filenames in the Terminal results in a bunch of ?'s as file names instead of the actual filename.
The fix is to run the ls -v instead of just ls command to "force unedited printing of non-graphic characters." Check the man page for ls for more information.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20021016070054400