What I'm trying to do is: use a standard sip based phone to call to a sip server which can serve a video file. This file can be local or stream from somewhere. Can flashphoner do what I want? My sip phone support H.263, H.264 codec. Audio 711.729.
Web Call Server 4 currently does not support file streaming as a SIP source.
As I see your case, you are going to make a call to PBX server and see video on your SIP softphone.
So you may consider other PBX which can do that.