I have been seeing the following warning message in application log of my exchange server 2003.
Event Type: Warning
Event Source: Server ActiveSync
Event Category: None
Event ID: 3033
Time: 8:48:32 AM
Computer: Server Name
The average of the most recent  heartbeat intervals used by clients is less than or equal to . Make sure that your firewall configuration is set to work correctly with Exchange ActiveSync and direct push technology. Specifically, make sure that your firewall is configured so that requests to Exchange ActiveSync do not expire before they have the opportunity to be processed. For more information about how to configure firewall settings when using Exchange ActiveSync, see Microsoft Knowledge Base article 905013, "Enterprise Firewall Configuration for Exchange ActiveSync Direct Push Technology"
Just wanted to know where in settings of PIX506e firewall needs to be changed.