Calls which fail in the ways described above will typically result in a server (GK, MGC, RS or Ps for example) in the network issuing a failure message. This message typically provides one of two options; call forwarding to a central answering position or call clearing. The message does not allow for any more intelligent decisions to be taken and information about the reason for failure is irretrievably lost. By enhancing the message with an indication of the reason for failure and an optional recommendation for handling, the processing of such failed calls may be improved. For example, a gateway which receives the failure message may simply act in the usual way and either forward or clear the call. However with the enhanced indication, it may instead choose to carry out alternative actions such as collect more digits and retry at end of dial. If overlap signalling is being provided and the IP cloud is not fully overlap compatible, the gateway might also do an overlap to en bloc conversion. Another option is to collect at least one more digit and retry the call. This typically works well if overlap signalling is not used.