Emulation of private branch exchange behavior

An apparatus and methods are disclosed for use by organizations that have PBXs at a plurality of sites. The invention pertains to cell phone calls from an to his or her "home" private branch exchange. For example, an employee who works at the Chicago branch office might call the Chicago office's PBX to invoke a feature such as setting up call forwarding, retrieving voice mail, etc. In the illustrative embodiment, such calls might be automatically and transparently directed to another PBX when it is advantageous to do so (e.g., for the purposes of security, reducing toll charges, because of unavailability of a particular PBX, etc.) Factors that might be used to determine whether to re-direct a call and to which PBX to re-direct a call include the day and time of the call, the network that the cell phone is currently connected to, etc.