title: Rails: delete a flash message inside a custom error controller
body: <p>I have a custom error controller to show dynamic error pages (for 404, 422,500, etc), everything works fine but I cannot delete a flash message (according to <a href="http://blog.plataformatec.com.br/2012/01/my-five-favorite-hidden-features-in-rails-3-2/" rel="nofollow">http://blog.plataformatec.com.br/2012/01/my-five-favorite-hidden-features-in-rails-3-2/</a>).</p>
  
  <p>Is there a way to delete the flash inside my custom error controller?</p>