%BNickServ ACC%B Returns whether the user using the given
nickname is recognized as the owner of the nickname.  The
response has this format:

    %Bnickname%B %Bacc-code%B

%Bacc-code%B is one of the following:

  0 - Nickname Unregistered
  1 - Registered, Offline
  2 - UnIdentified
  3 - Identified via password authentication
  4 - Identified via access list
  5 - Forbidden Nickname

Syntax: %BACC%B <%Bnickname%B>

