How to run a VMware image in Virtualbox

Having just downloaded Kali Linux I was wondering how to convert its VMware image to VirtualBox, thankfully I quickly found a page that just recommended to create a new virtual machine and add the VMware image as a disk:

So if you want to run Kali Linux in Virtualbox, just

a) Create a new virtual machine in VirtualBox
b) Slect ‘Use an existing virtual hard drive file’ and select the Kali-Linux image (e.g. Kali-Linux-1.1.0-vm-amd64, the one without -s00x in the name)

By they way, the default login for Kali Linux is root / toor