* @param event
*/
@Override
public void onNavigationEvent(NavigationEvent event) {
QName source = (QName)event.getSource();
QName target = event.getTarget();
InteractionUnit targetUnit = dialog.findUnit(target);
if(targetUnit!=null) // local to dialog
{
String suffix = target.getSuffix();
if(suffix !=null) // relative, local (#prev, #next)
{
if(NavigationEvent.RELATION.next.equals(suffix))
{