That's odd - the non-existent link I posted above is now not responding either.
It could be any number of things. Server move, internal routing issue, etc. and you'll need the Support guys to check on that stuff.
The only things I can think of at the moment that you can try yourself would be to check your .htaccess file (if you use one) and also open the domain settings in Panel and ensure there is no redirection set up in there somewhere. While you're in the domain settings part of Panel, hit the Change Settings button (even if you haven't changed anything) for the domain.