In case you have been following the iPhone jailbreaking scene, , you will be aware of the Limera1n bootrom exploit that is being used on the latest versions of RedSn0w to jailbreak iDevices. The exploit was discovered by George Hotz, aka GeoHot, and is a hardware exploit. This means, Apple cannot issue a software update to fix the exploit.
While Apple may be unable to fix the exploit on older iDevices, it looks like they may have taken to patching them at least on newly shipped models. An Apple customer who recently purchased an iPad realized that the jailbreak tools available in the market right now do not seem to be working with the new shipments. To be more precise, devices shipped after week 50 of 2010 appear to have resolved the issue.
If you are one who have purchased an iPhone, iPad or iPod Touch very recently and think you may have got a device with a new bootrom, you can confirm this by checking out Settings App –> General –> About –> Serial Number. Does it read something like xx050xxxxxx? Then, you may have a non-jailbreakable device.
We will wait for more word from the Dev team about how these users can jailbreak their iDevices.
Update from the Dev Team :
“the 2 times Apple has fixed bootrom so far, the bootrom version # changed too. This is still showing 574.4, so I wouldn’t worry.”