title: Flash messages not shown after redirect in MyFaces while it worked in Mojarra
body: <p>I've my own ExceptionHandlerWrapper to manage ViewExpiredException and other errors.</p>
  
  <p>The idea is to catch the error, add some error message and redirect (with a redirection, not navigation) to the index page, where the error message will be displayed.</p>
  
  <pre><code>    fc.getExternalContext().getFlash().setKeepMessages(true);
      Messages.addFlashError(null, "my message");
      Flash flash = FacesContext.getCurrentInstance().getExternalContext().getFlash();
      flash.put("foo", "hello");
      fc.getExternalContext().redirect("index.xhtml");
  </code></pre>
  
  <p>However, flash messages are not stored (but foo is present in the flash scope).</p>
  
  <p>This was working in mojarra, but I moved to myfaces 2.2.4 and it stopedd working. Any idea?
   (also using omnifaces 1.8.1)
  Thanks.</p>