iPhone 3G[S] freezes

[gtimus]

I have jailbroken & unlocked my iPhone 3G[S] using pwnage tool and blackra1n. However, when i switch it off and then back on, it gets stuck and displays the pineapple for a while then goes off and restarts showing the same thing the pineapple and it never turns on! Any ideas?

[revnja]

This is what is known as a 'tethered jailbreak'. This issue occurs on 3GS phones with a newer bootrom. Whenever the phone loses battery completely or is rebooted, you will have to connect it to a computer and use blackra1n again. The only thing blackra1n will do to an already jailbroken phone in your situation is boot it.

As of today, there is no fix or workaround for this issue.