Microsoft Knowledge Base Article 873214 contains the following introduction:
After you move a mailbox across an administrative group, any Microsoft Outlook profiles that were in use for this mailbox no longer function correctly. Mailbox servers can refer Outlook to the correct server after mailboxes have been moved within an administrative group, but this process does not work correctly for mailboxes that are moved across an administrative group. Security settings for e-mail mesages, calendaring, free and busy information, public folder moderation, and delegation may not work. You must update the profile for 100 percent functionality after such a move. A profile redirector tool has been created to address this situation. This tool is named the Exchange Profile Update tool (ExProfRe).
You can run the ExProfRe tool by using logon scripts or by using Group Policy. Or, you can run the ExProfRe tool at a command prompt to make the needed changes to an Outlook profile. The ExProfRe tool is a part of the Exchange Server 2003 Web Release. To obtain this tool, visit the following Microsoft Web site: