Can Media Center play Elementary Streams (MPV+MPA files)?

I have used CCE to convert some AVI files to elementary stream mpeg files
(where the video is stored in a .MPV file and the audio in a .MPA file).

Unfortunately, Vista Media Center does not recognize the MPV files. It
displays the .MPA files, but only plays them as audio files - it does not
play the corresponding video track.

Is there any way for VMC to play these elementary streams? Or will I have to
multiplex theminto a single MPG file?

Thanks.