i've got a long id3 TIT2 tag === TIT2 (Title/songname/content description): Every Little Thing She Does Is Magic but xfmedia just shows "Every Little Thing She Does Is", skipping "Magic". Artist is also relatively long (=== TPE1 (Lead performer(s)/Soloist(s)): Sting & The Police), but that shouldn't affect it.
it may be that the file has an ID3v1 tag as well as v2. v1 tags have a length limit, and libxine may be reading the v1 tag instead of the v2. either way, this isn't an xfmedia problem, i don't think.