linphone-2.1.1 has compatibility issues with ffmpeg which blocks video feature. That's a shame for an application calling itself "Open-Source SIP video-phone", isn't it ? ;) With linphone-3.0.0 (having video USE flag) stabilized I will be able to remove this old version of linphone. Thanks :)
amd64/x86 stable
Marked ppc stable. Closing this bug.