So you're saying I should just grab the first number at import time -- can do...

Well... I'd prefer you stick to spec and allow n/N. From 4.2.1 of the spec:

  TRCK
   The 'Track number/Position in set' frame is a numeric string
   containing the order number of the audio-file on its original
   recording. This MAY be extended with a "/" character and a numeric
   string containing the total number of tracks/elements on the original
   recording. E.g. "4/9".

If you just grab the first number at import time, then I lose all my carefully set track tags if/when I export (and JEmplode supports re-tagging from the database). Of course, if I could specify which tag fields to replace from the database when a song is downloaded, this might not bother me so much...

(And if you meant just grab the first number on import when it's outside the spec, then you can ignore all this. )