How to configure CommunicationError (Session Time Out)?

Hi,

Can we control the session time out or Communication Error (in the KNIME URL)?

In web.xml, aIthough default <session-timeout> = 30 mins, I did not see Communication Error in the URL even after keeping the session idle on webportal for close to 40 mins.

Is there any other server side configuration that determines server connection timeouts with the web browser session?

Thanks,

Swaroop