display message in chatbox?

is it possible for the admin to display a message in chatbox ;like follow rules so on

not like a message but like topic name

chat box canot see guests , so you can put rules on it but guests canot see rules .

well in chat it is hard to put any rules moreover guest cannot see the chatbox. Chat is too small to get rules in. But add rules in the forum about the chat. And whenver any one breaks paste the url in the chat with indicating the persons to see that