upgrading iphone 3gs (3.1.3) (5.12.01) to 4.0

[nefastus07]

Hi All,

I'm sorry if this has been asked a million times but I haven't updated my iphone since 3.1.3 and wanted to make sure that there's a unlock/jailbreak for the 4.0 version before going at it. I've read through a dozen topics and a bunch of tutorials/guides but none really fits my description. basically i have:

Iphone 3gs
Firmware: 05.12.01
Version: 3.1.3
using new boot rom as far as i know

At the time i think i used spirit to unlock the phone but can't remember.

i don't really care what version 4.0 i used since all i really need is to be on any 4.0+ (the stupid app i need requires 4.0+).

i've look through a bunch of guides and most were written around june/aug when there weren't any unlock/jailbreak for a new bootrom 3gs. So can someone here kind enough to point me to the right place so I can upgrade my phone. I need it to be able to unlock so that i can use t-mobile on it. Thanks.

[Mes]

Best best, use PwnageTool 4.1.2 (Mac) and follow this tutorial:

iClarified - iPhone - How to Jailbreak Your iPhone 3GS Using PwnageTool (Mac) [4.1]

Simple, no intermediate steps, and your baseband (and unlock) are preserved for now or a future sale.

[nefastus07]

thanks mes,

I just wanted to clarify, will using this program keep my current phone unlocked or do i need to use another program to unlock it? Also this is sure to work on the new bootrom right cause so far i've been hearing mixed suggestion from guides (not here but other websites). Thanks.

[Mes]

Yes, yes, and yes.

1. PwnageTool 4.1.2 jailbreaks to 4.1 iOS, preserves baseband (for the unlock), installs Cydia
2. Don't restore from iTunes backup just yet ...
3. Reboot. Run Cydia install essential (if any). Reboot
4. Run Cydia -- install UltraSn0w for the unlock. Reboot x2
5. Good to go....

Now --- last advice. When upgrading a major # (ie: 3.xx to 4.xx),it is better to set-up as new phone (iTunes) than to restore from backup.

[nefastus07]

ah thanks. but sadly i thought i can use windows for this but apparently not. i guess i'll have to find someone with a mac now. thanks for your inputs. though if you have a guide that uses windows i'll greatly appreciate it.

[eyeRobot]

If you want a custom firmware from pwnagetool send me a pm with your email, mention which firmware, which iphone and whether you want it activating. I can send you a link to download.

You will need the new redsnow to put your phone into a pwn'd DFU mode so that you can shift + restore to it without error on a PC.