session timeout handling

Is the "httpSession" object you're referring to a cookie set by the application? In a pure protocol sense, HTTP is stateless, so any "session" between a client and server would have to be maintained by some persistent object that the client sent back in each request (a cookie, a URI pattern, a header, etc.). In that case, what happens when the application session times out, that doesn't happen when it's behind the load balancer? Are you using any iRules? Have any specific or unusual configuration on the load balancer virtual server?