Since not everyone behaves well during chatting and playing, especially not on large anonymous networks, some help is available to privileged players for taming those who tend to be griefers.
Players can be silenced (gagged) with or without letting them know, which is a temporary measure. They can also be kicked off a server or even banned forever. In order to initiate an administrative action against a player, an ADMIN message is to be sent by the client. It will contain the name of the affected player, probably a reason for the action, and the admin sub-opcode which identifies the action. In response, the server will return a RESULT with action being set to "admin".
Sub-opcodes for admin actions are as follows:
GGZ_ADMIN_GAG silences the player. This works effectively like a global ignore list so that everyone but the player himself will not be bothered by his messages.
GGZ_ADMIN_UNGAG is the inverse of GGZ_ADMIN_GAG.
GGZ_ADMIN_KICK kicks a player from the server, i.e. closes the connection of the affected person.