I've been using antp for some time now. Great program btw

Because my stack of Xvid's grows alot, i was thinking to replace my Xvid (cd's) to Xvid (DVD's). Mulitple avi's on 1 DVD.
I made a list which has 1 number singed to 1 movie.
But if i have more then 1 movie on 1 dvd, i can't number everything like it should be.
Is is possible to number dvd 50 as, 50a, 50b, 50c,... or 50.1,50.2,... with all other futures? (import information of scripts,...)
Or can it be introduced?