Yeah you can, but you would have to call Cingular Customer Service and they will have your phone get unlock to work with T-Mobile SIM ... Well whatever Cingular's features may not work on T-Mobile network but works for voice...
__________________ bigbuck09@earthlink.net
EarthLink Revolves Around You
once you configure the phone then data, SMS, and MMS should work. If it accepts a tmobile SIM in a cingular RAZR then it us unlocked. Configute the phone over the air here. http://tmobileus.wdsglobal.com/phonefirst