Strange Message on Homepage. http://domaincom.www.domain.com/, does not exist.

Hey all,
I am getting the following line when I go to my main domain's home page. It reads.....

You are logged in already. No need to register again!
The site you were looking for, http://domaincom.www.domain.com/, does not exist.

Obviously the domain is my domain.

This is on the homepage of a new WPMS install. I currently only have the Ultimate Facebook Plugin installed. I am at Lunarpages where there was no other specific wildcard option apart from adding the *.domain.com sub-domain.

I get the feeling that I have missed a setting somewhere.
Any help would be greatly appreciated. Thanks in advance.