Hedwig is an open source IMAP, SMTP, POP3 server written in Java, designed with ease of installation and configuration in mind. Hedwig enables storage of mail message headers in a relational database(MySQL or Oracle) and mail messages in a file system.
Visit http://hwmail.sourceforge.net/ for more information.
An unofficial web console to administer Apache James 3 server
MOVED TO: https://github.com/fulvio999/jamesui
Jamesui is an unofficial web interface to manage and monitor Apache James 3 mail server.
It is written in Java and run inside Apache Tomcat.
SIMON is a very simple MTA and POP3 implementation. It is completely designed from the ground up and is useful for departmental or small to medium sized companies.