[SIP Beyond VoIP] Playback issue

[Flanagan, Stephen]

So we are sending an INVITE to the sylkserver in hopes that we can get a video playback. 
My playback file is a video. I have tried mp4, mov, avi. All with different resolutions and such. What happens is that we place a sip test call to test at test.com, the sylkserver answers  and then subsequently hangs up. When I play just a standard wav file from your /sounds directory this works great. 
If you could give me a pointer to some docs where / how to get this to work would be helpful please. 

Thanks,
Steve