my admin panel in google apps gives me this procedure to personalize my URL

Changing CNAME record
To use the custom URL ka.kolaboraccion.net, you must change the CNAME record with your domain host. Log in to your domain hosting service.
Navigate to your "DNS Management. The location and name of this page will vary by host, but can generally be found in Domain Management or Advanced Settings.  Find the CNAME settings and enter the following value for CNAME or alias:  ka, Set the CNAME destination to the following address: ghs.google.com Save changes with your domain host and click on "I've completed these steps."

I have not been able to find in my lunarpages panel any option for DNS management or CNAME settings.  Thanks fro your help.