A wireless telephone handset sends commands over a data network, and places voice calls over a telephone network, to a message storage system. The commands include information that enables the message storage system to identify the handset and correlate the voice calls with their corresponding commands....http://www.google.es/patents/US6553220?utm_source=gb-gplus-sharePatente US6553220 - Data network command packet and telephone network call integration in enhanced services system
Data network command packet and telephone network call integration in ...
