Outside of having the keyboard running an in-game macro, this would be illegal. Programming your keyboard would give you different capabilities than allowed by the developers - and so in my opinion would constitute an unfair advantage.
Then again, as long as you are sure that you wouldn't be getting any advantage, there isn't that much of a problem.
I'd head over to the macro subforum and learn how to write a macro, that way you are keeping definitely inside the bounds of allowed.
Sorry to be so goody two shoes about it
Edit have I really been posting here for more than a year? *sighs* Yeah, signing for DIYCE download won't waste any of my time at all