Elastix 2 4 0 Stable[64-bit]

Elastix is an open source unified communications server software that brings together IP PBX, email, IM, faxing and collaboration functionality. It has a Web interface and includes capabilities such as a call center software with predictive dialing.
The Elastix functionality is based on open source projects including Asterisk, HylaFAX, Openfire and Postfix. Those packages offer the PBX, fax, instant messaging and email functions, respectively.


http://www.elastix.org/

http://en.wikipedia.org/wiki/Elastix