This command will redirect all memos arriving to the nickname you are using to a new nickname that you specify. You need to be identified to both nicknames in order to enable this command. If you set MFORWARD OFF it will stop forwarding memos for the nick you are using. You cannot turn MFORWARD on if you have NOMEMO set on.
Examples:
/msg nickserv set mforward on JennAway
/msg nickserv set mforward off
If you have multiple nicks you will probably want to send most of your memos to one of them. This way you can check all of your memos at once. You might want to keep a nick's memos separate if you get different kinds of memos for each nick. But if you do, make sure you remember to read your memos for your less commonly used nicks.