X-lite does support video in the Windows version...but not Linux. Here is an old post of how to set it up using RTcom. I use it all the time to video conference while traveling.
http://talk.maemo.org/showthread.php...o+conferencing

I've had trouble when both devices are in the same network. I went next door to another network to test and it worked fine. N800(using RTcom) to my windows PC using xlite. Video and audio.