How can I emulate the keystroke perfectly?

OK, so I am not new at all to VB. I know all about sendkeys and a couple other ways to emulate keystrokes. But those methods are very ineffective for what I want to do... Here is what I want to accomplish:

There is a game that I want to send the "z" key to over and over again or hold the key down.
I wrote a program that could do this with SendKeys but the game doesn't let the sendkeys function even work.

For example: I have the game open and try sending keys to notepad, this doesn't even work with the game open... but works fine when the game is not open...

Please help me find another more reliable way to emulate the keystrokes so I can sendkeys to that game.
If this can't really be done in VB 6.0 I know other languages too so let me know if it can be done in another language.

I could be wrong, and it won't be the first time, but I don't think anyone here is going to aid you in developing a cheat for a game. Fact is, I think it violates the policies of the forum.

Cheat? I wouldn't be cheating.