Well, then I guess it's time to create a game-specific new spell called "Baldurs Magic Missile" that looks like and has the effects of the "old" Magic Missile ^^
I really loved that spell and I used it in 99% of the fights in BG1+2. I mean, you wouldn't presume to change a 99 Flake into lemon ice cream with a Hershey's Bar either ;-)
If the D&D rules state something different I get it, but the old BG-Magic Missile is still a well established, beautiful spell...