Just in from Kindle Blogs:
Many of you have been asking and I wasn’t able to give you an answer. Well… now that 2.5.2 is available for everyone to download from Amazon.com website, it’s official. Amazon has fixed the tarbomb vulnerability in the update installer. So jailberaking and hacking the Kindle is not possible now unless you are willing to mess with hardware or have something like telnet or “unbrick” hack (that doesn’t interfere with official updates) installed. If you do, then you should know your way around Kindle well enough to be able to replace fonts yourself. If you don’t then you’ll have to stick with reading Unicode on Kindle via PDF or figure out how to hack it for yourself.
As simple as UFH installation was, some people still bricked their devices with the old hack for one reason or another. So until a new method of jailbreaking the Kindle is found that is as simple as the old ones, I’m going to postpone UFH development.
Sorry, I wish I had better news for you.
Read more: http://blogkindle.com/#ixzz0qwiIaqPf