Default Generic.kl and hard key problems

Hey, hopefully someone can help me.

I just changed some parts of the file Generic.kl in the system\usr\keylayout folder to disable the wakeup funtion of the power button, when phone is locked. I wanted to use only the home button for this. I didn't work as I hoped and I replaced the edited one with the one of the backup. Now every change should be replace to original state, but I lost the funtionality of back and menu buttons.
The thing is, during the changes I used them very often and they worked. But after I used my backup, which is 100% the original one, it doesnt seems to work.

I have no idea, what did happen. anyone any idea?