Jftpgw is an FTP proxy/gateway that uses the FTP protocol (unlike those FTP
proxies that fetch an FTP file but work as an http proxy). You can use it to
make servers behind a firewall/NAT server (masquerading server) accessible
or to allow users behind such solutions to transfer files to and from the
outside of the LAN.
Jftpgw is highly configurable and can be run as a stand-alone daemon or 
under control of inetd. A wide range of options can be spedified per client, 
server or user. Other features are: support for a transparent proxy mode, 
forwarding, file caching, detailed logging, port ranges and session limits.

WWW: http://www.mcknight.de/jftpgw/
