You set the password with some sort of wand. When someone clicks it, it tells them to put in the password. If they get it right, onActivatePassword is called, if they get it wrong, onPasswordFailure is called.
It kinda sucks without having a clientcmd to bring up some sort of textbox, like the admin pass box or something.
Only way I can think of is clicking it, and it tells you to put a password in chat.