Looks like you aren't registered.
pick the nickname of your choice : /nick [yourname]
then registering : /msg NickServ register [password] [email]
replacing [password] and [email] with yours.
also you might want to get a cloak by asking nicely to the ops.
you can get a list of ops by typing : /stats p
EDIT : You might also need to identify each time you open your client :
/msg NickServ identify [password]
but most irc clients have an "autoperform" in the server options where you can put the command in.