Microsoft Exchange Server MAPI Editor
http://www.microsoft.com/downloads/details.aspx?familyid=55FDFFD7-1878-4637-9808-1E21ABB3AE37&displaylang=en
Use the Microsoft Exchange MAPI Editor to view and modify the contents of a Messaging API (MAPI) store directly.
Microsoft Exchange Server Quota Message Service
http://www.microsoft.com/downloads/details.aspx?familyid=EB52F6AB-E07A-476C-B32B-145AF6EA970C&displaylang=en
Use the Microsoft Exchange Server Quota Message Service to generate custom quota messages that inform users that they have exceeded their message quotas. This tools enables this task to be done without modifying DLLs, or without using an event sink.Quota Message Service is a mailbox agent, and it uses template messages to format the body of quota messages that it generates
More info: http://msexchangeteam.com/archive/2004/04/20/117024.aspx
- Joel