Known bugs: * it seems not to work with jdk1.1.7A VM. Fixed: * 1.0.11: received an exception: IvyClient.sendBuffer.write failed: Relais brisé (pipe) It happens while sending messages once a remote client has disconnected ( fixed in 1.0.12 ) Not a bug if you send a msg just after the start, it is possible that the message won't be sent. this is *not* a bug, but, hmmm, a feature. In fact, when you do start(), it triggers different threads, the broadcasts are sent, and it is possible that nobody has answered this broadcast by the time you start sending messages. Try adding an IvyApplicationListener with a callback on connect(IvyClient) to trigger the launching of messages