Downgrading iPhone 5 iOS 6.1.3?

I just bought a new iphone today and I would like to jailbreak it but there's no untethered jailbreak for 6.1.3 I obviously don't have a backup of the phone with 6.1.2 which does have an untethered jailbreak so I can't just restore from a back up. Is there anyway I can downgrade my iPhone inorder to jailbreak it? I'm pretty sure apple removed this capability a while back but i'm just making sure.

Not possible, apple no longer signs for that firmware.
next jailbreak will be a few months after ios 7 is released

  • Lost all downloaded apps from iPhone downgrading from iOS 7 Beta? Before I upgraded, I manually backed up my iPhone on my mac. I needed to downgrade after upgrading, so I opt+clicked restore iPhone and selected the correct firmware, 6.1.4 (for my iPhone 5). I loaded up the iPhone and restored from my previous backup. When I loaded up my phone, there were no apps on it that didn't come with the device! Does anyone know what went wrong or how to get all of the apps and their previous data back? It would help me beyond belief!
  • Is it possible to Lose iCloud Activation lock by Downgrading to iOS 6 on iPhone 4? I have a iCloud locked iPhone 4 which was factory unlocked. I hacktivated it using win SCP and now the sim won't work. So i thought why not downgrade to a version when Activation Lock wasn't even created. That way i will have a fully working iPhone on iOS 6 right? Is that possible?
  • Is downgrading the ios possible? I'm currently running ios 4.2.1 on iphone 4. I'm thinking of upgrading to ios 5.1.1 or even ios6 However, is it possible to go back to 4.2.1 if I encounter any problems with it?
  • Iphone 4 downgrading iso version to 5 rather than 6.1.3? Is there any way i can download my iso version of the phone i'm on 6.1.3 and i'm sure you can work out why i want to downgrade but i can't find a way on the net that does work, many thanks also it is on uk vodafone. Many thanks in advnace If i have what saved