I'm looking for a way to use mencoder to create an avi file with multiple audio.

I have an input file with multiple audio. I'm re-encoding the audio to mp3 format and copying the video stream (-ovc copy -oac mp3lame) I can select one of the audio tracks with no problem(-aid 0). But I would like mencoder to re-encode both streams and add them to the resulting avi.

By the way, I know I can use VirtualDubMod to re-encode, add the stream, add save the resulting avi. But I have a bunch of files to process so they are done throught a script. So using a single command line tool would be the best.

It is fine if I have to do it in multiple steps. As long as those steps are command line. For exemple, if there is a way to use mencoder to simply mux a stream in the avi, it would be fine.

Thanks in advance for any advices