To complete the confusion I should have mentioned that whereas in Jaunty the source packages are "ffmpeg-debian" (unrestricted) and "ffmpeg" (restricted), in Karmic they are "ffmpeg" (unrestricted) and "ffmpeg-extra" (restricted).
To complete the confusion I should have mentioned that whereas in Jaunty the source packages are "ffmpeg-debian" (unrestricted) and "ffmpeg" (restricted), in Karmic they are "ffmpeg" (unrestricted) and "ffmpeg-extra" (restricted).