someone lost a s710 and i found it outside of my work. I opened it and it was cingular, same as my provider. I turned the cell on and it says "Inactive SIM" so I'm guessing the phone has been missing for a while and the owner disabled her sim. My question is can i use this phone? I know all i have to do is install my sim card in it. But can I get into some kind of trouble for not turning it in? Can Cingular track me? If they can, is there a way i can prevent that? Please help.