form.add(backPanel);
form.add(deletePanel);
gridBuilder = new GridBuilder(form, "flowform");
final ContainerFeedbackMessageFilter containerFeedbackMessageFilter = new ContainerFeedbackMessageFilter(this);
final WebMarkupContainer feedbackContainer = new WebMarkupContainer("feedbackContainer") {
private static final long serialVersionUID = -2676548030393266940L;
/**
* @see org.apache.wicket.Component#isVisible()