installation of 8.04 fails

Wed Jul 9 20:22:42 UTC 2008

Hi
 When i try to install Ubuntu ver 8.04.1, the installation completes 
and  i get to the point of restarting the computer. When it restarrts i 
get the following error message

"Server authorization directory (demon/ServerAuthDir) is set to 
/var/lib/gdm  but is not owned by user 106  and group 114. Please 
correct the ownership or GDM configuration  and restart GDM"

How do i go about doing this?