Crazy problem here - Please help?

Hey Guys,

I was helping a friend to install some apps and widgets on her mac. One of the things I installed was the "Secondary TrackpadClick" package... after that it requested for a restart so I restarted it.

Now, the computer boots up and gets to the login screen... the trackpad responds but the keyboard is unresponsive.

Some of the keys on the keyboard work... like lowering or rising the volume (it even shows the animation on the screen) or changing the brightness... but the rest of the keys don't seem to do anything!

Please help, I am stuck at the login screen... everything else works, the lights light up, the controls work... but the keyboard keys (characters and numbers) are frozen. I can't log in because it prompts for the password and I can not type it in.

Any ideas?

I already tried resetting the PRAM and PMU, still the same.

Thanks for your help.