I've seen this posted over and over as well. It never seems to get resolved. I myself have gone and created a custom template, changed the port, expanded and restarted. The port in the proftpd.conf file shows as my new port, but you can't connect to it. It is still using port 21.
Has anyone been able to change the port and actually make it work??
Here is a snip of my proftpd.conf:
ServerName "ProFTPD e-smith installation"
ServerType inetd
UseFtpUsers on
User public
Port 10024
But I still have to connect on port 21....