Latest iphone 4.1 Activation Bypass tested with rebel Activation Products for all iphone models
Have you been caught out by itunes and has your software been updated to the latest OS 4.1 ?
If you know and possess a network sim of the same network as a locked iphone then you can activate using that. However if you dont know the network and dont have a network sim on that network the other option to use are the Rebel Activation cards to get in to any iphone and activate it.
http://rebelmicrosimcutter.com/iphone-2g-3g-3gs-4g-and-ipads-rebel-activation-card-itunes-en.html