1. Method for converting input messages from a plurality of different protocols, received by a message handling apparatus having a plurality of input ports, into a common protocol to allow processing of the messages using program data suitable for said conversion retrievable from a program data store, wherein when an incoming message arrives at an input port corresponding to the source of the message, a message object is created, the message object including a label identifying the respective input port, and wherein the program data is selected from the store according to the label indicating the input port.