This tutorial explains how to install and configure ProFTPD on Mac OS X 10.4 with MySQL 5.0 as the back end. I've tested this in a real production environment; it's really cool because your users are authenticated directly on a MySQL table.
[robg adds: Given the length and complexity of the tutorial, I decided not to try to replicate it here. We have, however, run a few other ProFTPd tips.]

