EPS (Email Parsing System) is intended to give people the ability
to write their own email processing tools. 
Whether you want to process incoming and outgoing emails, 
or just analyze a message,
this package is intended to aid in that endeavor.

Features

    * Written in C
    * API is documented
    * Fast and efficient

Usage
How we use EPS and how others use EPS

    * Tracking incoming and outgoing email messages based on threads
    * Archiving and searching against threads
    * Demographics collection via email
    * Email client
    * Create custom autoresponders
    * We even used it to parse simple LDIF files!

WWW: http://www.inter7.com/index.php?page=eps