The Kexec boot process has brought AOSP to many a phone! The Kexec boot process circumvents the locked bootloader to allow for full customization. Lately it has been ported over to several phones in the Droid Lineup. Developer "z4ck" has put the Kexec boot process to work to bring AOKP 4.1.1 Jelly Bean to the Droid 4! This is still a work in progress and there are quite a few bugs. The kinks are being worked out. This is however in no way a daily driver for now. It should also be noted that this should only be flashed via Safestrap 2.11 since it is the only recovery on the Droid4 to support Kexec. That being said you could always keep a stable stock build on your unsafe system and flash AOKP JB to your safe system this way you can always revert to stock for daily driver use, and the AOKP to mess around with!
Some things are working here, atleast enough to play around with the Rom. What's working includes WIFI, audio, data, hardkeys, keyboard, rotation and more. For now the list of what's not working is pretty long, but this is build 1. What's not working includes battery stats are messed up, the script takes a litte while to flash so you will need to be 100% charged, camera not included, vide camera will hot boot phone, arrow keys are mixed up, audio messes up and freezes phone at times. Of course Rom control, performance settings with overclocking, and tons more are included here.
Grab the Rom here