Ftp reverse proxy

[bordr415]

OK, so I've been reading for the better part of a couple days and still can't get figure this out…

I have a pfsense box (nothing special, basic setup) and an Apache server running as a reverse proxy for http to the other 19 servers.
Basically what I want to do is the same thing for FTP. As the people that are administering these servers can't ftp in to change any of the server files. (So everyone emails them to me and I spend my whole day doing their updates... >:()

Is there any way to get this done with pfsense or do I need to do something in Apache or do I need to find another solution. By the way, I only have 1 IP to work with.

I already know I could do different ports but am trying to keep it simple and on port 21 as all of the software and specialty apps require that port.

Any suggestions or solutions would be awesome...

Thanks in advance...