Postfix 3.7 MTA Released with OpenSSL 3.0 Support
Postfix attempts to be fast and secure, while at the same time being sendmail compatible enough to not upset existing users.
Exim 4.95 MTA Comes with a Bunch of Improvements
The latest version of the popular mail transfer agent, Exim 4.95, ships with TLS resumption support included in default builds.