1. A composite service enabling data processing system comprising: a plurality of channel servlets executing in an application server in a data processing system for storing and executing program code including at least one processor coupled to memory elements through a system bus, the servlets enabled to establish multiple, different channels of access to a common session for a composite service; a location registry comprising a table of entries associating the different channels of access with the common session for the composite service; and, a model servlet executing in the application server and configured for coupling to a model for the common session, for modifying state data in the model for the common session, and to synchronize views for each of the different channels of access to the common session responsive to changes detected in the model; and, a conflict detector for detecting collisions in concurrent requests to update the model for the common session by different ones of the channels of access, the conflict detector being coupled to the model servlet and enabled to permit updates to the model by individual ones of the channels of access without record locking through a comparison of a previous value of the model disposed in each of the concurrent requests to an actual previous value of the model.