Inserir componentes no JFrame com o contentPane setado

import java.awt.BorderLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JLayeredPane;

public class Teste
{
    public static void main( String[] args )
    {  
        JFrame application = new JFrame( "Programa" );
        JLayeredPane contentPane = new JLayeredPane();
        
        application.setContentPane(contentPane); 
        application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
        application.setSize( 600, 400 );
        
        application.add( new JLabel( "Mensagem central" ), BorderLayout.CENTER ); // nao funciona
        application.add( new JLabel( "Mensagem de fundo" ), BorderLayout.SOUTH ); // nao funciona
        
        application.setVisible( true );
    }
}