I haven't tried it yet, but doesn't it work off an R4 card instead of the Gameboy slot? I was thinking so, but could be wrong.
Alex Maul has a MAME emulator out there called Marca DS vidmouse, if you haven't tried it, that is still a work in progress. Some games have sound, some don't, but the ones that run well (Pac-Man, DK), run really well. He also has a great Atari Advanced emulator known as PokeyDS (I forget which Atari version though).
Frodo DS, the C64 emulator was hard for me to program, but once I got it, it works fairly well also....has been fun playing "Forbidden Forest", "Pogo Joe", and "Miner 2049er" on my DS!
And while I'm running my big mouth, I can't forget jEnesis....the newest version is the first Genesis emulator for the DS (to my knowledge) to have sound support...and quite frankly, it just rocks!

Wow - longer than I meant it to be...sorry!