Like qmail, Postfix is an MTA attempting to replace sendmail which is showing its age in the form of security problems among other things. From their Web site (www.postfix.org): ``Postfix attempts to be fast, easy to administer, and hopefully secure, while at the same time being sendmail compatible enough to not upset your users.'' Incidently, I'm a relative Unix newbie, and Postfix is the only MTA I found remotely easy to configure.