Xmail Log Archiver is exactly what it sounds like - a log archival system for XMail mail servers. XMail is a popular multi-platform mail server.
The tool not only places the expired logs into an archival directory with the ability to zip them, it can analyze the various types of logs generated via a modular reporting system. Thus, the postmaster can view statistics such as top HELO domains, top senders and so forth.
Written in PHP, the archival tool can be run on the many platforms that the XMail server has been ported to and can even run from an external machine.