Currently Being ModeratedMar 18, 2013 6:59 AM (in response to danguid)
Since the start of this issue coincided with your getting water on the trackpad, it is very likely that it is a hardware issue.
Contact Apple using www.apple.com/support/contact if you are in a country that supports it or call the appropriate phone number on this page. Alternatively carry the MacBook in to an Apple retail store or service provider to ask for a repair estimate.
Currently Being ModeratedMar 19, 2013 6:30 AM (in response to danguid)
Now it seems that the problem is solved.
Probably some residues of water are evaporated ... I can't explain.