Jailbroken Iphone 3GS 3.1.2 upgrade to 4.0.2 , and then down grade to 4.0.1

[aussiep]

Hi Guys, I need some help here,

I Have 3GS jailbroken/unlocked on 3.1.2 using blackra1n.
unlocked baseband 05.11.07

Now I wanted to upgrade to 4.0.2 (Latest firmware) using itunes

And then downgrade to 4.0.1 , and use the jailbreakme.com to jailbreak again and then unlock.



Is this possible, and I see this in My Cydia:

this device has shshs on file for iphone OS / IOS 3.1.3, 4.0, 4.0.1

So , with my little research , I think I can , but is there anything am missing here?

Thanks!..Please help me

[neodude237]

What's the point of going to 4.0.2, then downgrading to 4.0.1? Why not just go straight to 4.0.1?

[aussiep]

Can you please tell me how to go to 4.0.1..but I am not on offitial career, what would it require for me to activate My phone.

I was on official career, but now using another career, do I still need activation?

[mael]

Assuming you want to maintain your unlock/ultrasn0w, your only 4.0.x jailbreak solution is to go to 4.0 using a custom .ipsw built by pwnage tool or sn0wbreeze.

Pwnage tool guide (OS X): How to Jailbreak iPhone 3GS to 4.0 with PwnageTool | OS X
Sn0wbreeze guide (Windows): How to Jailbreak iPhone 3GS to 4.0 with Sn0wbreeze | Windows

Note: I could not get any .ipsw created by sn0wbreeze to restore, I had to create an image using pwnage tool on a mac, and restore using that ipsw on my PC.

Hope this helps.

Note that jailbreakme.com will jailbreak your phone but *will not* allow it to be unlocked.

[neodude237]

Can you please tell me how to go to 4.0.1..but I am not on offitial career, what would it require for me to activate My phone.

I was on official career, but now using another career, do I still need activation?

The sn0wbreeze method may work, but I've heard quite a few different stories about how well and.... how not so well the software works. So I can't really say anything about that. For jailbreakme.com to work, yes, you must be activated. It'd be easiest to get ahold of a friend's sim from an official carrier and just use that to bypass activation or pick up a prepaid one or something. Then run ultrasn0w in Cydia to unlock.