From Elendor
Syntax: +EXPUNGE [@<altname>] [<bboard name>] <message>
This command immediately and spontaneously eliminates a message whether or not
it's marked for deletion and whether or not you've even read it yet. If no
bulletin board is given, the message is deleted from your mailbox. If a
bulletin board is provided then it deletes the posting from the bulletin
board. The post must either be yours or you must be an administrator of
that bulletin board. Be very careful with this command. You don't get any
second chances here. Use +DELETE and +CLEAR instead if possible. Bulletin
board administrators: Remember to put the bboard name! Otherwise you'll
delete your own mail by mistake!
Example 1: +expunge 3
(Deletes your message number 3 from your mailbox immediately.)
Example 2: +expunge public 4
(Deletes message 4 from the public bulletin board.)