THIS SECTION IS OUT OF DATE. IT IS LIKELY THE CLIENT WILL BEHAVE DIFFERENTLY THAT DOCUMENTED HERE.
When adding a new property to an object that will fire property change events you need to be aware that the object will reside on the server and the client. There is nothing special to do when the object is on the server. However client side objects need special consideration. Since the server is in charge of updating the model the server side classes will fire property change events which are then sent over the network to the client. The client receives this property change events and then calls the update() method of the object whose property changes. Therefore it is important to write the statements in the update() method to handle the property that was added.