open source alternatives to Microsoft Exchange

Written by

Leic

in

OpenChange:

OpenChange aims to provide a portable Open Source implementation of Microsoft Exchange Server and Exchange protocols.

based on samba4

http://www.openchange.org/


Citadel:

turnkey open-source solution for email and collaboration

http://www.citadel.org/doku.php

Spicebird:

http://www.spicebird.com