Try using the following content from "Using ASP.NET MVC with Different Versions of IIS" @ http://www.asp.net/%28S%28ywiyuluxr3qb2dfva1z5lgeg%29%29/learn/mvc/tutorial-08-cs.aspx
Creating a Wildcard Script Map
If you don’t want to modify the URLs for your ASP.NET MVC application, and you have access to your web server, then you have an additional option. You can create a wildcard script map that maps all requests to the web server to the ASP.NET framework. That way, you can use the default ASP.NET MVC route table with IIS 7.0 (in classic mode) or IIS 6.0.
Be aware that this option causes IIS to intercept every request made against the web server. This includes requests for images, classic ASP pages, and HTML pages. Therefore, enabling a wildcard script map to ASP.NET does have performance implications.
Follow these steps to create a wildcard script map with IIS 6.0:
1. Right-click a website and select Properties
2. Select the Home Directory tab
3. Click the Configuration button
4. Select the Mappings tab
5. Click the Insert button (see Figure 4)
6. Paste the path to the aspnet_isapi.dll into the Executable field (you can copy this path from the script map for .aspx files)
7. Entery ".*" in the Extensions field
8. Uncheck the checkbox labeled Verify that file exists
9. Click the OK button