A new demo has been added in the Exchange Server 2003 demo portion.The detail of this demo is

Title: How to View Mailbox Permissions of a Specific MailBox-Enabled User in Microsoft Exchange Server 2003

Objective: The objective of this demo is to teach you how to view mailbox permissions of a specific mailbox-enabled user in Microsoft Exchange Server 2003. You can grant or deny permissions for mailbox-enabled users. You can then view permissions for a specific mailbox-enabled user.

If you are a subscriber, then click the Demos link in the navigation menu to view the complete list of demos.