protected void initialize() {
   super.initialize();
   this.selectedNodesHolder = new SimpleListValueModel();
   ListValueModel lvm =
       new ItemListListValueModelAdapter(
           this.selectedNodesHolder, ApplicationProblemContainer.BRANCH_APPLICATION_PROBLEMS_LIST);
   lvm.addListChangeListener(ValueModel.VALUE, this.buildBranchApplicationProblemsListener());
 }
 /** increase visibility slightly for listener */
 protected void branchProblemsChanged() {
   super.branchProblemsChanged();
 }