A computer-implemented method of, and system for, messaging in a computer network is disclosed. The computer network comprises at least two computer-based participant systems communicating through asynchronous exchange of messages. The first system maintains one or more data objects and notifies another system of modifications of the data objects by sending messages. Each time a data object is modified, the corresponding status object is updated and a modification status flag is checked. In response, a communication status flag is checked and a notification message is sent to the other system if necessary. The modification status flag is then reset. Upon receipt of a confirmation message from the other system, the communication status flag is then reset to the original status.