Syntax: DEL [channel] {num | list | LAST | ALL}
Deletes the specified memo or memos.  You can supply multiple memo numbers or ranges of numbers instead of a single number, as in the second example below.
If LAST is given, the last memo will be deleted. If ALL is given, deletes all of your memos.
Examples:

  DEL 1
      Deletes your first memo.

  DEL 2-5,7-9
      Deletes memos numbered 2 through 5 and 7 through 9.