I tried to follow the instructions in this link.
https://www.mobileread.com/forums/showthread.php?t=88004
Unfortunately when I "Update my Kindle" I get an error message U004.
My Kindle Keyboard has both WiFi and 3G capability.
It is running Version 3.3 of Kindle
The first few digits of the serial number are: B006 A0A0 ...
I used "update_jailbreak_0.11.N_k3g_install.bin"
And installed it to E:\ of the drive that appeared on my Windows Xp desktop.
I assume this is the root directory ?
Just in case, I also tried resetting the Kindle to the factory defaults, but no luck ...