@Stojke: Emulator for one devices or several devices? Can you dump the firmware from those phones, or download it from somewhere? Anyway you'd have to deal with the whole UI of the phone just to play the game. And probably not one phone model contains all such games, so you'd have to point the emulator to another firmware to play a different game (installing software is possible for Java programs, but I don't know if the built-in games are written in Java and are available outside the firmware).
I suppose a port is the easier way.
@kolano: The emulator is indeed for Symbian based phones which definitely are smartphones (although some people may not see all of them as smartphones because a lot of them don't have touch screens).