I just bought the at&t blackberry curve 8330 and i wanted to use it with boost mobile can anyone tell me if thats possible and i have the sprint blackberry curve 8330 but there is no sim card so is it possible to unlock that as well and use it with boost mobile? Because i took it to a local cell phone store that unlocks phones and he said that it was impossible for him to unlock the sprint blackberry curve 8330 without the sim card . I would really appreciate some help and thank you!!!!!