title: visual studio - strange error on extension method
body: <pre><code>Error   1335    The call is ambiguous between the following methods or properties: 
  'Wedding.Helpers.ModelStateExtensions.GetFirstErrorMessage(System.Web.Mvc.ModelStateDictionary)' and 
  'Wedding.Helpers.ModelStateExtensions.GetFirstErrorMessage(System.Web.Mvc.ModelStateDictionary)'    
  C:\Documents and Settings\Administrator\scratch\Archant\WebSites\Weding\Areas\AddressBook\Controllers\Partner\HomeController.cs 
  31  69  Wedding
  </code></pre>
  
  <p>it's pointing to the exact same method on the conflict!!</p>
  
  <p>Why oh why?!</p>