Currently Dynamic Mail is still in development and there are no public versions available, but in it's current state SMTP sending works, POP3 receiving works, the minimal text file based mail storage plugin works and the basics of the user interface are in place.
A new MySQL backend plugin has been implmented by Ken Ames and myself. It has been tested using MySQL 3.23, 4.0, 4.1 and 5.0 on OS/2, Windows and FreeBSD.
In the future more mail sending/receiving protocols will be added, as well as plugins for storing mail in databases or other pre-existing data storage facilities.
Dynamic Mail is currently being tested on OS/2, Windows, FreeBSD, Solaris and Linux. A MacOS X port is in the works.
Here are some screenshots of Dynamic Mail 0.1 in action.