The Mac OS 9 Finder uses Apple-specific Mac OS character sets (such as MacRoman or MacJapanese) to enter and display file names. The Mac OS X Finder uses a worldwide standard character encoding, named Unicode, to enter and display file names. Mac OS 9 converts file names to Unicode for storage on Mac OS Extended volumes, but when the encoding differs from the system default (for example, a Japanese file name on an English system or vice versa) the conversion to Unicode can be incorrect. As a result, the file name may not display as expected. The Mac OS X File Name Encoding Repair utility will correct many of the common cases of incorrect conversion.
Mac OS X 10.1,
Mac OS X 10.2