Abstract: The present invention provides improved communication systems and call processing methods wherein each subscriber to a multiple directory number per line (MDNL) type service and to a message storage and retrieval service individually selects how these two services will interact. Specifically, the subscriber has the option to set control data for selecting which directory number the switching system transmits at the time of forwarding calls to the system which provides the message service. If the subscriber selects a first option, the switching system transmits the directory number actually dialed to the message service system. If the subscriber selects a second option, the switching system transmits a predetermined one of the assigned directory numbers to the message service system. In one embodiment, the system also offers the subscriber a third option.