title: RedirectToAction and Routing not passing parameter correctly
body: <p>I am trying to use a RedirectToAction method after a selfposting Action (which passes IsValid). The redirect happens fine but the parameter I am attempted to pass to the action is always null.</p>
  
  <pre><code>[HttpPost]
  public ActionResult UploadForm(UploadFormViewModel formVM)
  {
          if (!ModelState.IsValid)
          {
              return View(formVM);
          }
  
          return RedirectToAction("UploadConfirm", new { confirmVM = new UploadConfirmViewModel() });
  }
  
  public ActionResult UploadConfirm(UploadConfirmViewModel confirmVM)
  {
          return View(confirmVM);
  }
  </code></pre>
  
  <p>And here is my routing</p>
  
  <pre><code>        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
  
          routes.MapRoute(
              "UploadConfirm",
              "{controller}/{action}/{confirmVM}",
              new { controller = "EnrollmentUpload", action = "UploadConfirm" }
              );
  
          routes.MapRoute(
              "Default", // Route name
              "{controller}/{action}/{id}", // URL with parameters
              new { controller = "EnrollmentUpload", action = "UploadForm", id = UrlParameter.Optional } // Parameter defaults
          );
  </code></pre>