Then I agree with hacky. I call that the ANAC. I thought you were talking about the call announcement almost all LEC's and LD carriers use, which is based on the incoming CID.
EDIT: to add all the 958 CO codes are long gone around here and other areas I've worked in. It's now either an office code other than 958 or a toll free number that needs a password. Some of the milliwatts and quiet terms remain but that's about it.
