Sending and/or receiving messages in a computer system having memory and a processor. The method includes configuring the memory to have one or more streams connecting a generic messaging client to send messages to and/or receive messages from one or more protocol-specific messaging clients. The streams are formed by providing configuration data comprising one or more destination definitions. Each of the destination definitions corresponds to one of the protocol-specific messaging clients. Each of the destination definitions has a specified messaging protocol and one or more stream definitions. Each of the stream definitions has parameters associated with the specified messaging protocol of a corresponding one of the destination definitions. In code for the generic messaging client, at least one stream object is provided specifying one of the destination definitions and one of the stream definitions.