Difficult Question

Hi there,

I have a problem that maybe someone who is smart can help me with. Currently I have an Iphone 4 running on the At&t network that I bought through Apple. Everything works fine on it.


I am about to buy another Iphone 4 on Ebay. This one is on the process of "connect to Itunes and enter last 4 digits of SSN to activate and such".


Does anyone know how to activate the second Iphone 4? Would I be able to take out my sim card from the first one and put it in this one? Any help would be nice.



Thanks