mencoder -oac copy -ovc copy mf://*jpg -audiofile audio.mp3 -o out.avi
or with resolution and fps
mencoder -ovc x264 -oac copy mf://*jpg -mf w=1280:h=960:fps=25:type=jpg -o out.avi
mencoder -ss 00:00:00 -endpos 00:02:18 -oac copy -ovc copy in.avi -o out.avi