title: System.Configuration.ConfigurationManager not available?
body: <p>In a VS2005 C# project I have added a reference to System.configuration.
  In the object browser, I can see the System.Configuration.ConfigurationManager.
  In Intellisense System.Configuration only has the old ConfigurationSettings, and not ConfigurationManager.</p>
  
  <p>My code 
     System.Configuration.ConfigurationManager.AppSettings["MySetting"]</p>
  
  <p>is highlighted as a syntax error and does not compile.</p>
  
  <p>In a different project, the exact same setup works just fine... any clues as to what is going on?</p>