Open Source NetBSD Mail Transfer Agents

Email2Fax and Fax2Email gateway for Asterisk, that could be integrated to your own existing Asterisk.

This is a milter which scans emails with CRM114

Your own mailing system (most easiest to use with zero configuration) for the entire world (available in almost all the languages of the world) which will include Mail User Agent and Mail Transfer Agent thus trying to give maximum speed while transferrin

This is a milter which scans emails with qsf (Quick Spam Filter)

Rumble is a mail server suite for SMTP (ESMTPSA), HTTP, POP3 and IMAP4v1 with an extensive C/C++ and Lua API for scripting. It comes with support for SSL/TLS, SQLite and MySQL and has a web-based administration and webmail feature. Additional included modules feature greylisting, DNS blacklisting, SpamAssassin support and dynamic performance scaling as well as a multithreaded structure that allows for clustering of multiple servers for one or all domains, and with the ease of the Lua API, you can create your own new server mailing lists, CRM software, e-marketing and other extensions within minutes.

dspam-filter is a filter to invoke the anti-spam tool DSPAM directly from the embedded maildrop in vpopmail via dot-qmail forwarding. DSPAM masquerades as the email server's LDA. However most users of Qmail prefer to leave the qmail-queue intact.