I received my new rooted unlocked samsung captivate today and took it into the at&t store to get a SIM card. After the SIM card was installed the at&t employee could not activate the phone. She tried another SIM card but still couldn't get service to the phone. She even pulled a SIM card from one of the working demo phones to no evail. The AT&T store manager stated that it was a problem within the phone itself. Any ideas? 