Новая версия Zoiper SoftPhone.

ZOIPER SOFTPHONE NOW SUPPORTS T.38 FAX OVER IP

Zoiper 2.0 IAX & SIP softphone (previously known as Idefisk) now supports T.38 Fax over IP. Zoiper is a VoIP soft client, meant to work with Asterisk and SIP-capable IP-based communications systems and infrastructure.

Zoiper is available for Windows, Mac OS X and Linux.

http://www.zoiper.com/free.php