WSRP | Portlet Caching

Hi,

I m Weblogic Portal 9.2 MP1. The portal application consists of pageFlow
Portlets and now migrating to the Federated portal.

The issue which we are facing is when navigating through the pages if we perform
some operation on let's say page1 and then navigate to page2 and if we comes
back to page1 then the last operation result which we did on that page persists.
Let's say if we are performing some search operation then those search results
will be available if we come back to same module.

This is not a caching a issue as i have already set CachingExpires to -1. The
problem is when second time i m going to the page 1 navigational state is being
sent because of that last results are displayed.

How can i avoid to sent back the navigational state?

Thanks in advance