False logouts after 15 seconds of idleness
 

We have our VB install behind a load balancer. After turning on FORWARDED_FOR header inclusion (and logging in to the forum), occasionally a page will load in such a way that the server thinks you aren't logged in. The loadbalancer keeps the sessions open in a persistent manner, so the problem isn't that the request is being sent to another server in the cluster. If you click on another link or refresh, it will load the page as normal, with you logged in.

This is occurring roughly after 20 seconds of idle time, if the idle time is less then 20 seconds, the login request does not come up...If we turn X_FORWARDED_FOR off, this glitch doesn't happen, but then most of the users are being seen as having the same IP address, that of the LB... presenting other problems.