I don't use a passcode but tried 'Erase all content and settings' and right at the very end it prompts for my Apple ID 
Since my iPhone 4 was jailbroken and Cydia holds the shsh files to 6.1.3 I wonder what happens if I try a dfu restore to 6.1.3, if it can still be activated?
Since my iPhone 4 was jailbroken and Cydia holds the shsh files to 6.1.3 I wonder what happens if I try a dfu restore to 6.1.3, if it can still be activated?