So I got an iPhone 4 (att) from a friend of a friend and unfortunately there was a passcode and I didn't know it. I'm new to the iphone and jailbreaking and such so I made the mistake of restoring the iPhone on my computer. Now it is requiring a sim card that I do not have. I originally bought the phone because I am on T-Mobile and would like an iPhone. I found a tutorial on how to "hacktivate" using redsn0w. After I hacktivate the phone, can I then unlock it to use it on T-Mobile using SAM? Quick tips would be helpful as well! thanks!