Amazon’s current lineup of Kindle Fire HD tablets are somewhat hobbled by locked bootloaders.

Of course, that hasn’t stopped modders from rooting the tablet and installing Google’s Play Store. And as we previously reported, Kinfauns of XDA Devs recently came up with a method for Fire HD owners to backup and restore system software – without having to perform a custom recovery.

Essentially, the backup and recovery process involves a shell script that’s able to create a backup directory on an inserted SD card. While this may be useful as a stopgap measure, modders and devs alike have been waiting for a full-on bootloader bypass that will allow for custom recovery and the installation of custom ROMs.

And now hackers at XDA Devs have figured out how to get around the locked bootloader and install ClockworkMod custom recovery, which makes it easier to load custom firmware on the tablets.

As Liliputing’s Brad Linder points out, the above-mentioned method is somewhat different than “Safestrap” project which has apparently been temporarily put on hold – yet seems to use the same Cyanoboot bootloader developed for last year’s B&N NOOK Tablet.

“[The Nook is] another device with a locked bootloader, [although it] has been running custom ROMs for the better part of a year,” Linder explained.

“The next step is building custom versions of Android (or other operating systems) that play well with Amazon’s latest tablets – [and] developers are already working on that [as well].”

Indeed, developer verygreen has posted instructions for building an unofficial version of CyanogenMod 10 for the Kindle Fire HD 8.9 using software based on Google Android 4.1 Jelly Bean.

As expected, CM10 for the Kindle Fire HD 8.9 is still in the very early stages of development. As such, audio doesn’t work, video playback isn’t functional, Bluetooth and the camera don’t work, and there’s no support for the sensors – so automatic screen rotation is non-existent.

However, CyanogenMod does load on the tablet and is partially usable. WiFi works, as does the Google Play Store and Android apps.

Meanwhile, an XDA modder by the name of reverendkjr is coding a port of CyanogenMod 10 to work on the 7 inch Kindle Fire HD, which varies enough from the 8.9-inch version in terms of both hardware and software that it requires its own custom software.

The CyanogenMod 10 for the 8.9-inch seems to be in a pre-alpha stage, as almost nothing works, not even the touch screen.

Nevertheless, work is progressing steadily on both CyanogenMod 10 ports. We will keep you posted.