postfix-policyd-spf-perl is an RFC-4408-compliant SPF policy service for
postfix written in Perl.
python-policyd-spf is a Postfix SMTPd policy engine for SPF checking. It is
implemented in pure Python and uses the python-spf module.
Mixmaster is an "Chaumian mix-net" anonymous remailer. Remailers provide
protection against traffic analysis and allow sending email anonymously or
pseudonymously.
Postgrey is a program which implements greylisting and is
designed to work with the Postfix MTA.
The MailHost product provides support for sending email from within
the Zope environment using MailHost objects.
This is python module for RFC 5451 Authentication-Results Headers
generation and parsing.
It also supports Authentication Results extensions:
RFC 5617 DKIM/ADSP
RFC 6008 DKIM signature identification (header.b)
RFC 6212 Vouch By Reference (VBR)
draft-kucherawy-dmarc-base-00 DMARC
cyruslib is wrapped interface for imaplib.py, it adds support for
cyrus specific commands. Function naming is the same of cyradm
A port of GitHub's Email Reply Parser library, by the fine folks at Zapier.