How do I cancel an e-mail that is scheduled but not yet delivered?

Using Outlook 2003, Exchange 2003 Server. Sent an e-mail message that was
scheduled for delivery a couple of days later. It shows in my sent items in
Outlook.
Now need to keep this message from being delivered at all. How?
-Delete from Sent Items? Will deleting it from sent items get rid of it or
is it already in the exchange server waiting to go?
-Recall the message from Sent Items? Won't this send the message and then
send a prompt message asking user if allright to recall? If so this is not
what I am looking for. I don't want the message delivered at all now.