README & wiki page only indicate that something 'recent' is required, but doesn't specify what versions of ffmpeg and ffmpeg2theora must be used.
ffmpeg2theora (current in Ubuntu 11.04) gives:
/usr/bin/ffmpeg2theora: unrecognized option '--two-pass' /usr/bin/ffmpeg2theora: unrecognized option '--buf-delay' File `256' does not exist or has an unknown data format.
FFmpeg version 0.6.2-4:0.6.2-1ubuntu1 seems to go ok (currently I error out on permissions, but that'll be a problem elsewhere).
Before deploying, ops will need to know what versions to package etc.