You might already have proftpd installed, but not running. Two ways to run it; run it standalone, in which case you'll have to prod xinetd into ignoring it; or managing it through xinetd, in which case you'll have to prod xinetd into doing it's job(xinetd runs network services when needed instead of on startup).

I don't like xinetd. xinetd does inexplicable things like letting you connect then booting you instead of refusing your connection, and never seems to log error messages at all ever.

If I remember correctly, xinetd stuff is configured through files in /etc/xinet.d/ , look for a proftpd file in there. To start proftpd manually, /etc/init.d/proftpd start . To set it up to automatically run on boot, see man chkconfig.