Take it out of the bloody fridge!
Lay out some kitchen paper or a towel and carefully take the phone *completely* to pieces: Cover, screen, rubber button thing, battery, sim, big microchip, speaker etc, and leave overnight. My sister's came apart and went back together really easily.
My sister dropped her phone onto concrete into a puddle and I managed to get it to work once it was dry. About 4 months later the battery kept coming loose and Nokia refunded even though it had to go to the factory to be examined, they didn't say anything about it having been taken to pieces.
If it's old, it's worth a shot as you'll probably have to buy another anyway.