Linux PupupMenu CheckboxMenuItem Bug

Does anybody know how to resolve the following Linux problem? I am
unable to get events from a checkbox item in a popup menu under Linux.
The problem seems to be unknown to other Java versions. Of course,
using JFC would resolve the problem, but I want to stay with AWT for
some reasons.

Thanks a lot foa any constructive answers.

---------------------------------

import java.awt.*;
import java.awt.event.*;

public class PopupTest extends Frame
    implements ActionListener, ItemListener
{ PopupMenu PM;

    public PopupTest ()
    { super("Popup Test");
        setSize(500,500);
        setLocation(200,200);
        addWindowListener(new WindowAdapter ()
            { public void windowClosing (WindowEvent e)
                { System.exit(0);
                }
            });
        addMouseListener(new MouseAdapter ()
            { public void mouseClicked (MouseEvent e)
                { clicked(e);
                }
            });
        PM=new PopupMenu();

        MenuItem item1=new MenuItem("Item 1");
        PM.add(item1);
        item1.addActionListener(this);

        // buggy code?
        CheckboxMenuItem item2=new CheckboxMenuItem("Item 2");
        PM.add(item2);
        item2.addItemListener(this);
        item2.addActionListener(this);

        add(PM);

    }

    public void clicked (MouseEvent e)
    { PM.show(this,e.getX(),e.getY());
    }

    public static void main (String args[])
    { Frame f=new PopupTest();
        f.setVisible(true);
    }

    public void actionPerformed (ActionEvent e)
    { System.out.println(e);
    }

    public void itemStateChanged (ItemEvent e)
    { System.out.println(e);
    }
}