Abstract: A data communication system routes calls from a mobile communication device associated with a calling party to a mobile communication device associated with a called party. If calls are not answered by the called party, a call is routed to a voicemail server. A data channel is opened between the mobile communication device associated with the calling party and the voicemail server over which higher fidelity audio signals are transmitted. The transmitted audio is supplied to the voicemail server for conversion from an audio to a text format. In accordance with another aspect, a data channel is opened with a call placed by the calling party. The data channel is used to append information that is sent with a call to give the called party information regarding the call or the caller without having to answer the call.