You might be able to use an SMTP event sink _vbscript_ to append this.
But, can you not simply use the (unique) message-id header that Exchange appends to emails?
From: exchangelist-bounce@xxxxxxxxxxxxx [mailto:exchangelist-bounce@xxxxxxxxxxxxx] On Behalf Of Ahmad
Sent: 29 January 2008 09:14
Subject: [ExchangeList] Outgoing mails Auto Reference Number
We are using Exchange 2003 on windows 2003 server ..we need to add auto genarated numbers in every outgoing mails of all the users for tracking purpose .. is there any special software for this ..or it is possible from Exchange sever itself .. please help me out ..
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