title: josso bypasses javax.servlet.Filter when redirect to back_to page
body: <p>In our app (service provider), there is a security filter to prevent viewing certain pages. For example a user can view a.xhtml but not b.xhtml. The user can login to view a.xhtml. And if he type in the URL to b.xhtml, the security filter will redirect himi to an error page.</p>
  
  <p>Using josso, before login, user may type the url to b.xhtml and would be redirected to josso login page. After successful login, user will be redirected to the "back_to" page, which will be b.xhtml. In this case the security filter is not triggered, the use can see b.xhtml!</p>
  
  <p>Refresh on b.xhtml then will trigger the filter and send user to error page, but too late.</p>
  
  <p>We use josso 1.8.5 and tomcat 7.0.26.</p>
  
  <p>Please any guru can help?
  Thanks</p>