Very good suggestion, and I thought about using that method at first. Then it turned out we'll have so many missiles this might not work out. The problem is: Every player can buy his missiles, his ammo. That means every time he buys ammo the game would have to freeze. I guess I could use this method, but I really would prefer another one... thx though!
~"I never let school interfere with my education"~ -Mark Twain