.gba to .nds?

Just a thought I had, would it be possible in any way shape or form to create something that would convert .gba roms to .nds roms which the DS would then think were ds games and play as such (just with one screen blacked out the entire time), thus allowing people without slot-2 cards to play gba games?

I'm sure there are tons of holes in the concept, but I'd like your opinions or explanations as to why it wouldn't work.