hi, i used this guide How to convert DivX/XviD with AC3 to a DVD with AC3 and subtitles

but now i see that my movie hasn\'t got ac3 but MPEG Layer 3

i already used tmpgenc to put my movie to m2v
and i\'m working in tmpgenc dvd author for the moment

but what do i have to do with my audio file?
do i have to open virtualdubmod and save it as another extension?

cheers, sam