Free end-to-end encryption code?

As a side project, to support remote mail and news pickup through the Internet to my company's servers (through a firewall), I've been slowly writing an end-to-end encryption program. Essentially, the idea

Sounds like something that could be directly done with ssh [http://www.cs.hut.fi/ssh] using TCP/IP forwarding. I've myself used it to encrypt the connection to the smtp port on a remote server. I configured sendmail to use "localhost" as the major relay host, disabled the sendmail daemon, and ran sendmail from cron to process the queue every now and then. Incoming mail was fetched via ssh from a remote file server using a couple of small scripts. Tatu