You might want to check that you have the V4L and/or V4L drivers installed for your camera. I've never used skype, so I don't know how the video streaming goes, perhaps it's in a format that requires some type of codec on your computer... Sorry, I really don't know hardly anything about this.
If you want to make sure that it's not just your camera config, download gqcam, and test the camera.
It could also just be a bug in skype, though it's not likely, because most linux support for stuff like that is usually beta-ish, though I'm not sure about skype.
Anyway, search around w/ google. You never know what you may find.