1. A high-performance mail transport agent Postfix is Wietse Venema's mail transport agent that started life as an alternative to the widely-used Sendmail program. Postfix attempts to be fast, easy to administer, and secure, while at the same time being sendmail compatible enough to not upset existing users. Thus, the outside has a sendmail-ish flavor, but the inside is completely different. This package does not have SASL support. For SASL support, install postfix-tls. From Debian 3.0r0 APT

2. Postfix is a Mail Transport Agent (MTA), supporting LDAP, SMTP AUTH (SASL), TLS and running in a chroot environment. Postfix is Wietse Venema's mailer that started life as an alternative to the widely-used Sendmail program. Postfix attempts to be fast, easy to administer, and secure, while at the same time being sendmail compatible enough to not upset existing users. Thus, the outside has a sendmail-ish flavor, but the inside is completely different. This software was formerly known as VMailer. It was released by the end of 1998 as the IBM Secure Mailer. From then on it has lived on as Postfix. This rpm supports LDAP, SMTP AUTH (trough cyrus-sasl) and TLS. If you need MySQL too, rebuild the srpm --with mysql. From Mandrake 9.0 RPM