ffmpeg failure

I recently installed ffmpeg (and gentoo for that matter, which is why the post
to the newbie list) to try to do some video capture, and get an error message
"Could not init video 4 linux capture: disabling video capture"
I am able to capture to an .avi file with xawtv, so I know that my v4l driver
for the bttv card in my machine is working, but I'd like to capture directly to
mpg so that I don't have to deal with the huge avi files. Am I missing a
simlink or something as simple? Does anyone have a clue as to what I need to do?