Laptop disfuntion

My friend and I was drinking some beer and he unfortunately spilled his beer on my Dell Inspiron 8100 laptop.. We tried to clean it and dry it and I shot it down and we went out to drink some more.. when I came home the next morning and turned it on the keyboard was f*cked up..
Most of the keys didn't work and some of them even typed other letters than they where programmed to..
We thought it was just a case of buying a new keyboard for the laptop, but when we got it and installed it - it worked fine for 5 minutes and then went crazy again.. for an example the 'i' button is the 'right mouse key'..
I phoned Dell Technical Support and they said it might be a motherboard issue..
Now Im concerned if they're right or just trying to get some more money out of me.. I was told by my friend, of course the guy who spilled the beer that this couldn't be the answer..
If anyone of u have knowledge to this kind of issue please help me