Abstract: In an improved cellular telephone network, which in the illustrated embodiment, is a roadside emergency callbox system, and in which each cellular callbox includes programmable circuitry for call progress processing, various tones transmitted in a telephone exchange are detected, decoded and responsively acted upon by the callbox according to program control. Each callbox is further capable of receiving and decoding DTMF tones from the telephone exchange to allow arbitary information, including alphanumeric information for local display at the callbox, to be received and interactively processed subject to on-site program control. Still further, each of the callboxes within the cellular network can be remotely programmed by a maintenance computer to call a newly designated telephone number in the event of activation of the callbox which can be utilized in the case of the need for extraordinary emergency response.