iPhone 4 unlock help

[Mindwaste]

Hey guys a quick question I have:

iPhone 4 - iOS 4.0.1
Baseband: 01.59.00
Carrier: T-Mobile (ultrasn0w)
SHSH: iOS 4.0.1, 4.0.2, 4.1, 4.2.1, 4.2b3

I wanted to upgrade to 4.2.1 while preserving my baseband. I wouldn't bother updating but some new apps require 4.2 now. Could anyone please point me in the right direction as to how to upgrade to 4.2.1 while retaining the ability to jailbreak and unlock.

Thanks in advance!

[iYeow]

You can only preserve your baseband of 1.59.00 by using Tss Server with save 4.1 blob in Tiny Umbrella. Restore to stock 4.1 using TU to verify when restoring in itunes.
Once you have restored to 4.1, you can jailbreak it with Limera1n.
Don't restore to 4.2.1, it will not preserve your baseband, even if it did, you will end up in recovery mode again because fw 4.2.1 has a baseband check, if it the bb doesn't match the firmware, it will either freeze up your iphone or you will end up in recovery mode.

[babyblue_pimp]

There's also custom firmware made with pwnage tools. Although 4.1 is the highest ATM

[Mindwaste]

Thanks I'm going to try this so basically use tiny umbrella to do shsh even though cydia has it? Download 4.1 and restore to that. Jailbreak and unlock and everything is gold!

[Mindwaste]

Do you all know where I can get 4.1 from because iTunes will restore to 4,2.1 and what do you guys think about the SAM method for activating. Thanks!

[nebo1ss]

You can update to 4.2.1 on the iphone 4 and preserve your 1.59 baseband using Tiny umbrella but you must not use the restore option use the update option.

If you use restore it will lock up your phone and you will not be able to kick it out of recovery. You have to launch TSS service in Tiny umbrella and then just select update in Itunes. You will get an error but will be able to kick it out of recovery. Remember use update not restore.

You can check with the developer of Tiny umbrella if you want confirmation of my instructions.

However, you should be aware you will have a tethered jailbreak until the DEV team irons out the problems with the Redsn0w untethered jailbreak and that assumes you have the 4.2 beta hashes.

[Mindwaste]

Oh perfect thanks man that was really helpful. Is 4.1 jailbreak untethered as well?

[i.Annie]

Yes 4.1 is untethered.

[cyps86]

How did you go mindwaste? I'm looking at doing the same thing and would appreciate some pointers..