I have an AT&T Samsung Jack. I would like to use this phone on other carriers such as T-Mobile, etc. Is it possible? Can I use AT&T Samsung Jack on other carriers? If yes, how can I use it on other carriers? What all do I need to do switch to different carrier? Can anyone help me regarding this? I would really appreciate if someone can assist me on this. I hope to hear real soon from you guys out there. Thanks.