PSTN functionality is enhanced by the addition of an external service bridging device (ESBD) between one or more devices, e.g., signal switching points (SSPs), and a service control point (SCP). The ESBD serves as a coupling device to one or more control devices, e.g., other SCPs or IP servers, in addition to the SCP. To support the passing of messages between the SS7 network and the control devices, the ESBD includes message reformatting capabilities. The ESBD monitors for messages directed to SCPs and/or replies to messages directed to an SCP. In response to detecting a message the ESBD checks to determine if the detected message is to be processed or simply forwarded to the SCP. Messages to be processed are intercepted, duplicated, modified, replaced, broadcast, redirected, etc. Replies to broadcast query messages are detected and processed so that a single reply, in the format of an SCP response, is returned.