The first form returns a message corresponding to that mail message number in your mailbox. This function can be used to forward mail, or as a way to simply transfer mail messages to attributes on an object.
The second form returns three numbers, corresponding to the number of read, unread, and cleared messages <player> has. The third form returns <player>'s <mail message #>. It works like the first form except it applies to another player. The last form returns the number of messages the evaluating player has. Only wizards can use the second and third forms of the function on other players.
(--Soylent 02:16, 3 December 2005 (EST))