Webaccess problem with automatic logout.

After changing the "timeout for inactive sessions" in console one at "Properities of GroupwiseWebAccess Agent" to let say 600
and the same in file webacc.cfg "Security.timeout" to 600. After approximately 30 minutes when we go back to the page where groupwiseweb site is loaded we will see only empty "client" without messages and personal data. We can go throught all
options and nothing we will see but all the time we are logged.

Can anybody know where problem is or may be ?