jftpgw

jftpgw is a proxy server for the FTP protocol. It is highly configurable, allowing you to use an XML-like configuration file to define almost any combination of the client's IP, the server's IP, the user name, the destination port, and so on. jftpgw supports inetd/daemon mode, transparent proxying, forwards, caching, logging, data IP and port specification (port ranges), limiting of the number of simultaeous sessions, and several proxy login styles for clients that support FTP proxies.