Unable to charge

My wife spilled some water on her Pebl and she shut it off for the night. She dried it pretty good but it had a protective case over it and she thought that it didnt get water into the inside of the phone but it did. The next morning the phone wouldnt work. We left the battery out all day and yes, the "wet" dot had turned red. We thought all was lost, but that evening after it had dried we replaced the sim card and battery and turned it on and it worked fine....except it needed to be charged and when she went to plug it in we got the "unable to charge" msg and the phone shut off. Well, since I had bought the phone second off of Ebay I knew there was nothing that Cingular would do, I took the screws out of the back and took the phone apart. There is another one of those dots back there as well....and it wasnt tripped. I did notice a little bit of white stuff around were the battery prongs touch the main circuit board, I gently used the small screw driver I used to take out the screws and cleaned that stuff off. I also gently scraped those prongs and the metal they touch on the circuit board. Thought it was a long shot but I put the phone back together and plugged it in and bygod, its charging. Guess we will see how long this fixes the problem. Hope this helps you out some.