Ok, so I have an iPhone 3G & am on a family plan with my mom & dad. I wasn't upgrade eligible, but my mom was. I ordered the iPhone 3GS online from the Apple Store using her line. Now the problem is that she has a Samsung Blackjack & she does not want my iPhone 3G. When the iPhone 3GS comes, is there anyway that I can take the SIM out & put mines in, and then activate it, so that my mom can keep her Blackjack?