In order to do this, you will need to seperate names. The same name cannot be logged in with the @ and with out the @. You will need to chose which you use for what. Then you open the chatroom and log in. You then again open the chatroom in another window. This should work.

A oper @ can also be logged in, at one place, only once and does not need to be an operator. The only way for the person to be oped is for them to put in their op information.