title: Rails 3 cross subdomain flash message
body: <p>Is it possible to set a flash[:notice] message that would be set in a controller on www.example.com but would be read and rendered on client.example.com?</p>
  
  <p>In this particular instance, www.example.com and client.example.com are in the same Rails 3.2 application.</p>
  
  <p>A user is coming in via www.example.com/signup, completing a form and then being redirect to a newly created subdomain client.example.com.</p>
  
  <p>Can you do something like:</p>
  
  <pre><code>flash[:notice] = "hello world", domain: "*.example.com"
  </code></pre>