
Electronics companies plan to use military technology, developed to protect soldiers from chemical attack, to make mobile telephones and other equipment waterproof.
The technology involves an invisible coating that is chemically bonded to the surface of the instrument, repelling water and preventing it from seeping into the device where it could damage circuitry.

while searching google i found handcellphone that Fujitsu F730i is already waterproof. More photos are available there.
I wont recommend these phones to anyone , else you wont have escape with your office phone calls even while taking a bath. Anyways, jokes apart, with so much technology advancement, I dont think it will take much time for cellphones to go waterproof, and Fujitsu has already done it. I think Nokia , sony , samsung and Motorola will follow soon. What do you think ??? :)