A system and method to detect and provide information related to slamdown calls placed to a subscriber's mobile device. In one embodiment, a who-called server is implemented as part of a GSM network that uses a CAMEL protocol. The who-called server receives a CAMEL-based trigger when an incoming call placed to the subscriber's mobile device is deflected to a forwarded entity. In some instances, the who-called server ensures that the incoming call was deflected because the subscriber's mobile device was unreachable. The who-called server then determines whether the calling party abandons the incoming call before incoming call is answered by the forwarded entity. If the calling party does abandon the incoming call, the who-called server captures the calling party's identification information. The who-called server, in some instances, transmits the identification information to the subscriber after the subscriber's mobile device switches from the unreachable state to a reachable state.