How works .mu3 playlist file ?

Hello

I synchronized an iTunes 3 playlists on my F5X+ via GE. Then 3 .m3u files are created in /Music folder. But I am not able to select one this playlist (no playlist available said the player in Playlist menu).... I assume it's a bug from Mac GE...
Are PC user there ? Could you please have a look to your playlist file (if it works !!) ?

Thx