G webmaster tools report error, how should I handle it?

Hey

I've added a website to the Google Webmaster Tool, which report this:

Website is indexed as http://mydomain.com/, not as http://www.mydomain.com/. If you wish to show all the data for the website, you have to add and confirm http://mydomain.com/...

What shall I do here? Remove the website from googlewebmaster tools and readded it again? I tryed looking in the google help but didn't find anything there

Add and confirm both?

I just ran into this like 12 hours ago. I added http://mydomain.com and it now works fine.