I'm developing the system like you need (in the main features). We're ready to make an adaptation for your requirements.
The main features are:
generation and transfer of voice notifications with notification listening time supervision;
interaction with the subscriber by means of voice interactive menu (IVR);
generation and transfer of text notifications;
answerphone for call acceptance;
mass notification of people in case of emergency situation.
The system has the following inherent features:
notification campaigns creation and management;
creation and management of schedules for notification campaigns;
routing of the notifications delivery which includes selection of the optimum channel by different criteria (cost, loading, quality);
prioritization of messages delivery by different criteria.
Integration and reporting features:
program interface SOAP for integration with external systems;
direct integration with databases;
report designing about results of operation in the given format.