/mcpBlock the incoming collect call based on the category II-8 which is received from the telco switch. This is the default mechanism and all Cisco Gateways perform this without any configuration. This method of blocking requires a newer telco switch which supports category based marking. To disable this method use the command collect-call-enable on the cas-custom group. 1. Utilize the double-answer feature on an r2-digital E1 R2 cas-custom group. The double-answer configuration disables the category based blocking, and replaces it with the double-answer feature. This works by first answering the incoming call and starting a 1 second timer. After 1 second, the gateway sends a release in the form of a CLEAR BWD command. The Telco can then send a CLEAR FWD to the gateway and the call can disconnect. A timer starts after the gateway sends the CLEAR BWD, and if this timer expires, the gateway sends another ANSWER signal thus assuming the call is not a collect call and from here the call proceeds as normal. This timer can be configured using cc- reanswer-to within the the cas-custom group. 2. Category II-8 Block message (debug vpm signal)