Maybe the dns manager for mirc.com could add forums.mirc.com to point here, as using the sites ip address points it in the right place (you aren't logged in because your authentication is set with a cookie relevant to 'forums.mirc.com' only), so there doesn't seem to be an issue with virtual servers.

The site uses 'complete' hyperlinks (in that all links will put you back on forums.mirc.com) however.