I have tired to find a way to do this and failed, so I thought I'd ask if you have a solution.
Our public website is hosted by a company that hosts many sites on the same server/IP. As I understand it, they distinguish between sites by looking at the URL you send. So, if I'm anywhere but inside of my corporate network, I can type http://www.mydomain.com to see my web page. The browser providers are now treating WWW as a trivial sub-domain and stripping it off of the start of a website URL, The problem it creates is, if I'm inside of my corporate network, www.mydomain.com gets changed by the browser to mydomain.com which resolves to my domain controller. I see no way to distinguish between someone wanting to get to my domain controller and the outside website. When they didn't elide the trivial sub-domain, a record in my DNS zone for WWW would send users to the outside website. I should mention that I have an IIS server on my domain controller. It supports maintenance of a 3rd party application.