Right Aligned ToolBar Control - Spacer issue

When adding a right aligned control to a toolbar I have to add a sping/spacer as described here - however, when an overflow button appears the spacer component is selectable in the overflow popup menu. Is there any way to avoid this behavior? The test below demonstrates the issue.

//see: http://www.oracle.com/technetwork/articles/java/javafxbest2-1634274.html
//section: Implementing Springs and Struts in the UI
public class ToolBarOverflowTest extends Application
{
  public static void main(String[] args)
  {
    Application.launch(ToolBarOverflowTest.class, args);
  }
  @Override
  public void start(Stage stage)
  {
    System.err.println(System.getProperty("javafx.runtime.version"));
    ToolBar toolBar = new ToolBar();
    for (int i = 1; i<6; i++)
      toolBar.getItems().add(new Button("ToolBarButton " + i));
    Region spring = new Region();
    HBox.setHgrow(spring, Priority.ALWAYS);       
    toolBar.getItems().add(spring);
    toolBar.getItems().add(new Button("Right ToolBarButton"));   
    BorderPane root = new BorderPane();
    root.setTop(toolBar);
    Scene scene = new Scene(root, 400, 300);
    stage.setScene(scene);
    stage.show();
  }
}