I recently upgraded from Java 1.4.2 to 1.5.0_03 on a Red Hat 9 system.
When I compiled and tested an existing program that worked fine under
1.4.2 I discovered one small but significant problem.

I am using a JWindow for the main window of an application for its
clean look, because I am emulating a radar screen. Since I can't use of
a menu bar, I use a pop-up menu on a right-mouse-click to configure the
application. One of the menu selections is supposed to show a JDialog
to perform various configuration functions. If the program compiles and
runs under 1.5 the JDialog fails to appear (nothing at all seems to
happen).

If I compile and run the same program under 1.4.2, it works fine, and
the dialog appears. If I change the JWindow to a JFrame, the dialog
appears under either 1.4.2 or 1.5.

Is there some problem with this feature under 1.5? I am doing something
stupid that is causing the dialog not to appear under 1.5 (but somehow
slips through under 1.4.2?)

Here is a sample program. It uses buttons to show the dialog instead of
a pop-up menu, but the effect is the same: under 1.4.2 the dialog
appears; under 1.5 it does not. If the JWindow is changed to JFrame,
the dialog appears in either case:

// DialogTest

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

//public class DialogTest extends JFrame    // works under 1.4.2 or 1.5
public class DialogTest extends JWindow     // works only under 1.4.2
{
 JDialog dialog;

 DialogTest()
 {
   // create main window
   JPanel buttons = new JPanel();
   JPanel content = (JPanel)getContentPane();
   content.setBackground(Color.white);
   content.setPreferredSize(new Dimension(400,400));
   JButton help = new JButton("Help");
   help.addActionListener( new ActionListener() {
     public void actionPerformed( ActionEvent e )
       { show_dialog(true); }});
   JButton quit = new JButton("Quit");
   quit.addActionListener( new ActionListener() {
     public void actionPerformed( ActionEvent e )
       { System.exit(0); }});
   buttons.add(help);
   buttons.add(quit);
   JLabel text = new JLabel("Application",JLabel.CENTER);
   text.setPreferredSize(new Dimension(300,300));
   content.add(text,BorderLayout.CENTER);
   content.add(buttons,BorderLayout.SOUTH);

   // create help dialog
   dialog = new JDialog();
   Container dcon = dialog.getContentPane();
   dialog.setTitle("Dialog Test Help");
   JButton close = new JButton("Close");
   close.addActionListener( new ActionListener() {
     public void actionPerformed( ActionEvent e ) {
       show_dialog(false); }
   });
   JLabel htext = new JLabel("Help text.",JLabel.CENTER);
   htext.setPreferredSize(new Dimension(200,100));
   dcon.add(close,BorderLayout.SOUTH);
   dcon.add(htext);
   dialog.pack();

   pack();
 }

 public void show_dialog( boolean b ) { dialog.setVisible(b); }

 public static void main( String[] args )
 {
   DialogTest dt = new DialogTest();
   dt.setVisible(true);
 }
}

Thanks for any assistance or enlightenment. I am going to go back to
1.4.2 for now, but would like to re-migrate to 1.5 in the future.