You can assign up to 10 Automated Attendant extensions. An Automated Attendant extension is one that sends the caller to one of the four Automated Attendants. You can also administer a Directory Listing or Recorded Name.
Refer to PARTNER Messaging Planning Form 2 Extension Administration for the Automated Attendant Assignment information identified for your site.
To assign an Automated Attendant extension:

Procedures
Assigning Mailbox Extensions
Assigning Transfer-Only Extensions
Assigning Fax Extensions