I got root on Diablo by installing Openssh. Once its installing, it will ask you to enter a new root password then you can use that. Make sure you have Openssh client as well.

Use the following on the Terminal:
ssh root@127.0.0.1

(type "yes" when prompt)
[password]
enjoy!

It also works well on KDE

Root on Konqueror (File manager/browser)

On Location/address bar type:
fish://root@127.0.0.1
[password]
enjoy!


Linux Rulez!