Chatroulette uses Flash. Flash webcam support was disabled due poor performance.

"
Camera support in Flash was intentionally disabled. it was actually technically working at one point (accidentally). among other things, [Nokia are] afraid of pages managing to get users to accidentally enable the camera and the privacy concerns that entails."

More
http://maemo.org/community/brainstor...flash_plug-in/
http://talk.maemo.org/showthread.php?t=40097