the auto attendat aasimple.aef (system) has 3 prompts 1- dial by number, 2- dial by name, 0 for operator
how to define the operator extension number
Use aa_sbcs_v02.aef. You have more options available to you in CCA. This screen shot shows you what it would look like.
To get here, in CCA 1.9.1, go to Configure -> Telephony -> Auto Attendant