Since there's no actual Keyboard on PPCs, just the SIP which sends keyboard input messages to windows, I don't think there's any way to stuff it in the way you're thinking.
However, you should be able to queue up a large number of keyboard messages, etc, to simulate the same thing. Obviously there's some problems with this, but I'd look into using SendMessage for WM_Keydown/WM_Keyup/WM_Char, etc messages to your app.
