When an Automated Attendant detects a fax call, it transfers the call to a specific Fax extension or Hunt Group. In order for this to occur, you must first identify a Fax extension. See Assigning a Fax Extension. Then, you must use the following procedure to assign the Fax extension to one or more Automated Attendants.
Do not assign a Fax extension to an Automated Attendant if you are using the Fax feature available with PARTNER ACS Release 3.0 or later.
PARTNER Messaging allows a maximum of one Fax extension per Automated Attendant. Multiple Automated Attendants can share the same Fax extension.
To assign a Fax extension to an Automated Attendant:

Procedures
Modifying a Day or Night Menu
Creating a Submenu
Creating a Submenu to Play a Directory List
Modifying a Submenu
Deleting a Submenu
Creating Announcements
Modifying an Announcement
Deleting an Announcement
Programming the Schedule Options
Administering a Temporary Schedule
Programming Line Assignments
Assigning a Fax Extension
Deleting a Fax Extension