Model MC319LL, Downgrade to 4.1

[iLawCDN]

Hey all,

I have an iPhone 4, model MC319LL, currently running a non-jailbroken iOS 4.2.1.

Since RedSn0w is still in beta, I would like to use limera1n and iOS 4.1 to jailbreak the phone.

I have successfully downgraded from 4.2.1 to 4.1 on my OTHER iPhone 4, model MC605C.

When I try to downgrade the MC319LL, it says "This device isn't eligible for the requested build", even in DFU mode...

How can I get around this? I've only jailbroken my MC605C, so I'm a little new at this. Step by step instructions would be greatly appreciated.

[Stray]

Do you have your 4.1 shsh's saved. Check with this program. You will need to download it. The Firmware Umbrella - TinyUmbrella

[iLawCDN]

I don't have the shsh's saved. The phone was swapped by Apple for the Proximity sensor issue and came with 4.2.1 on it. is there a way of spoofing and/or copying a different one?

[Stray]

No sorry. The only way is to have your 4.1 shsh's saved and apple stopped signing the firmware.

[iLawCDN]

Is there any way I can use my shsh's from the MC605C on the MC319LL?

[Stray]

No. It's shsh is only for the device that has it. For example I have on 4.1 and 4.2.1 shsh's saved. So I can only restore to those 2 for my 3GS for my other I have everyone possible.

[iLawCDN]

ok thanks for your help.