assistance with encrypting droid razr maxx

[lowlow]

i have a rooted(stock) Verizon droid razr maxx running 4.1.2. I want to use full disk encryption on my phone. I have watched some youtube videos and did some research first. all the tutorials say it will take at least an hour to complete and is not reversible. when I do it however, it only takes about 2 minutes and it does give me an option to decrypt. but, it never asks for the encryption key when rebooting. it says it has completed successfully, but again, it never asks for a key when powering on multiple times. I have downloaded and installed: "cryptfs password" from the play store, and, it too says "device not encrypted, exiting". i'm at a total loss here. does anyone know a fix for this, or know of a good FDE app? or can it be done manually from terminal emulator? thanks.