My 3G is still on 4.2.X so this may only be for 3Gs and newer devices. You may be able to un-brick it by downgrading if you are a developer, I know I've switch

My 3G is still on 4.2.X so this may only be for 3Gs and newer devices. You may be able to un-brick it by downgrading if you are a developer, I know I've switched versions several times, including recovering from scary notices like the phone only wanting to say 'connect to itunes'.