The remote method that "does all the work". This won't get
called until the client starts up.
System.out.print("Adding client " + da);
try {
System.out.print(" from ");
System.out.print(getClientHost());
} catch (Exception ex) {
// nothing
}
System.out.println();
list.add(da);
// exportObject() returns the Stub; we return it to the client.
return UnicastRemoteObject.exportObject(da);
