problems with a drowned iPhone 3GS

Hello everyone!

Got myself a problem=( My friend dropped his phone in a sink with water. After letting it dry in rice he discovered that there was no sound from the speaker, the battery didnt hold the charge, etc, so i suggested to buy the whole housing assembly... It arrived a few days ago, i was very excited to replace it, but when i did so I discovered that there still was no sound and no the power button didnt work too. On top of that there s no sound from the headphones!

everything else seems to work fine...,volume buttons, battery,cam....

So does anybody have any ideas?Oo

Cant throw it away=( its 32gb!