GNU Anubis is an outgoing mail processor. It goes between the MUA and the MTA, and can perform on the fly various sorts of processing and conversion on the outgoing mail in accord with the senders specified rules, based on a highly configurable regular expressions system. It operates as a proxy server, independently from mail user agents.
GNU Anubis can edit outgoing mail headers, encrypt and/or sign mail with the GNU Privacy Guard, build secure SMTP tunnels using the TLS/SSL encryption even if your mail user agent doesnt support it, or tunnel a connection through a SOCKS proxy server.
