1)   sharpVoice(tm) Client 6.0
sharpVoice is a internet telephony program that enables free PC-to-PC and inexpensive PC-to-Telephone voice conference calls even with slow internet connections.

 2)   Voicent VoiceXML Gateway 6.0.1
VoiceXML Gateway VOIP PSTN TAPI development SDK for interactive telephony apps. High level W3C development platform. Supports text-to-speech, voice recognition, DTMF tones for both inbound, outbound apps. Works with VOIP, Skype, and voice modem.