Changing host name. Need to use non standard format (include "." mark)

Hi, I need to change the host name of my pc to include "." (the desired host name is "Something-Or-Other.engad.foe.auckland.ac.nz (http://en-252268.engad.foe.auckland.ac.nz)") However when trying to change my host id I get the following error "the new computer name entered is not properly formatted. Standard names may contain letters (a-z, A-Z), numbers (0-9), and hyphens (-), but no...