The first sentence of the "Unsubscribing from Mailing Lists" section of majordomo's response to "help" command contains a typo.
>Your original intro message should contains the exact command It should contain, not "contains". Also, according to the message lists owners' addresses must be of the form: >listname-ow...@openbsd.org >This is the address of the person or persons who maintain the >mailing list. But, at least when you subscribe to the @misc you receive a message from the owner-m...@openbsd.org.