Iphone unlock

[Collegebound]

So, I have an iPhone 3gs with bb 5.13.04 and it's currently unlocked for T-mobile on 4.0. I was wondering how would I go about in unlocking it for 4.2.1 if I follow the green poison guide? As of now, I haven't heard anything about ultrasnow updating or anything, so I'm sort of lost. Thanks in advance.

[i.Annie]

You must upgrade to 4.2.1 with a custom firmware to preserve the baseband. Then run greenpois0n to untether the jb and install Cydia.

[Collegebound]

Ah, alright. Is there a windows version of pwnage tool or something related to it to do this? I don't have access to a mac.

[i.Annie]

There is no windows version of pwnagetool. You will have to search for the custom firmware. Be sure it doesn't include the iPad baseband.

[Collegebound]

Hmm, ok. Thank you.

[i.Annie]

No problem