Possible to upgrade jailbroken/unlocked 3GS to iOS4?

[iPhonelover2010]

Hello,

I recently got my hands on a jailbroken/unlocked 3GS running 3.1.2. Is it possible to upgrade it to OS4 without losing the jailbreak/unlock? Warning: I'm a newbie, so you may have to break it down lol

Thanks in advance!

 

[dhlizard]

Hello,

I recently got my hands on a jailbroken/unlocked 3GS running 3.1.2. Is it possible to upgrade it to OS4 without losing the jailbreak/unlock? Warning: I'm a newbie, so you may have to break it down lol

Thanks in advance!

Nope, upgrading removes jailbreak and software unlock. If it's old bootrom and pwned jailbreak (not Spirit), you can upgrade and jailbreak in one operation with a Pwnage Tool custom restore IPSW.