A method of provisioning a gateway (80) is provided in a telecommunications network including a circuit-switched network (90) and a packet-switched network (70). The gateway (80) bridges calls between the circuit-switched network (90) and the packet-switched network (70). The method includes: receiving a registration message from consumer premises equipment (CPE) (60), the message including an address for the CPE (60) on the packet-switched network (70); determining a directory number (DN) for the CPE (60); placing a probe call to the determined DN over the circuit-switched network (90); receiving a call from the circuit-switched network (90), the call being terminated at a call reference value (CRV); recognizing the received call received from the circuit-switched network (90) as the probe call; capturing the CRV at which the probe call is terminated; and, associating the captured CRV with the address for the CPE (60).