SJphone
SJphoneŽ is a VOIP softphone that allows you to speak with any other softphone running on PC/ PDA, any stand-alone IP-phone or using VOIP service provider with any traditional wired or mobile phone. It supports both SIP and H.323 standards and is fully inter-operable with most major VOIP vendors and Service Providers.
http://www.sjlabs.com/sjp.html

Xten Eyebeam
Xten's long awaited Video SIP softphone application is now available. Supporting open standards for VoIP, Video and Instant Messaging.
http://www.xten.com/index.php?menu=products&smenu=eyebeam

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