im no expert but i would say your w580i will slowly die unfortunately,in my experience any phones i have got wet in the past have started working again only to slowly over 6 months go wrong then die all together.

I have been told that if you get a phone wet there is a way of saving it but only applies if you do it straight away (within 24hrs),it's got something to do with stripping the phone down to the circuit board then soaking the board in a weak acid soloution to undo any damage the water has done to the board,wether this is true or not i dont know.

Have you tried holding down 2 and 5 instead of C then connecting your phone?