webcam in skype ok but not in gimp

[Adam Hardy <adam.ant@cyberspaceroad.com>]

I got myself a webcam to skype, and plugged it in the usb port and it works fine 
with skype, but i want to grab an image from it in gimp or with w3cam or vidcat 
and it doesn't work.

in gimp, i don't even think i'm in the right menu but i can't find any other 
menu option than "file / acquire / xsane / device dialog" which gives me the 
error "failed to open device v4l:/dev/video0: invalid argument"

I can understand that since gimp is probably looking for a scanner but I see 
other documentation on the net showing gimp with a dialog box showing a mix of 
scanners and webcams.

In skype, the config shows the webcam under devices as "UVC camera (046d:09a4) 
(/dev/video0)" so I'm at a loss now.

I tried v4l-conf but that just seems to be for settings on the camera itself, 
not the OS config.

Any inspirational advice thankfully accepted

Adam