I cannot, as I am not logged in and cannot do that. But I think it is OSX 10.7 Lion. Memory is 256 mb, processor I do not know.
I just tried with an extaernal USB keyboard and that worked.
Version is 10.7.1
Processor: 2.4 GHz Intel Core Duo
Memory 250 GB
So my conclusion is that it is mechanical, hence fix the keyboard.
I had already done that.
Solved the problem this way: Removed the shift keys and cleaned below. Put the keys back! And it works!