JBoss EAP HTTP Sessions are not expiring or timing out as expected.

Issue

• The session expiry time has been specified in the application's  web.xml, but the actual time the session getd invalidated seems random. There are cases where it is still active after a couple of hours.  The web.xml contains the following:

  <session-config>
      <session-timeout>30</session-timeout>
  </session-config>
  

• Jboss is not cleaning up the expired sessions even after the timeout value for the session has reached

• Sessions are expiring prematurely for certain applications.  End users are getting kicked out of their session before the predetermined 30 minutes.  It is as quick as 2 minutes, depending on seemingly random activity.
• We are facing frequent session timeouts in our application which is deployed over JBoss EAP 5.1.2 and having JBoss EWS as front end web server.