Installing Multiple Web Sites in IIS7 for Cognos 10

[footyref]

We have a requirement, as we did in Cognos8.2 using IIS6, to create three different web sites, BIC, BICTST and BICDEV, so that all a user had to do was type one of those in their browser and it would be directed to the gateway servers and then to the correct web site and use the Cognos installation for that web site to direct them to the correct Cognos Configuration.  That worked in IIS6, but is not working in IIS7 and Cognos will not assist any further because their documentation only shows how to set it up from the Default Web Site and use different BIC, BISTST and BICDEV virtual directories.

Has anyone had any experience doing what we are trying in IIS7?  Please help if you can.  It definitely works the way they document it, but that is not the requirement we have and since it worked in IIS6, we are being told to make it work the same in IIS7.