ODBC and ipchains packet filter

I have a linux server with mySQL behind a linux packet filter. My users want to update the database with ODBC connects from their windows boxes. Which ports in which directions have to be open to allow this? I opened 3306 already, but this seems not to be enough. mfg ar -- mailto:andreas@rittershofer.de http://www.rittershofer.de PGP-Public-Key http://www.rittershofer.de/ari.htm