When I close an window by clicking closing button at the top-right of that,
an exception has occurred and stack trace is output.

1. Reproducing process
 
When created window object by "new" and lightweight component is put on that,
Focus does not move to the lightweight component bu "requestFocus()".

1. Reproducing process

 1) Compile the attached java program, "Applet1.java"
 2) Invoke "appletviewer Applet1.html"
  -> You can see a window that includes the "DISPLAY WINDOW" button.
 3) Click the "DISPLAY WINDOW"
  -> You can see a new window which has a blue squre and "request focus"
      button.
 4) Click the "request focus" some times
  -> you can see the color of square changing blue and red.
 5) Click the closing button at the top-right of the window.
  -> You can see the following message.

I:\focus-no-return>appletviewer Applet1.html
requestFocus() to MyComponent[,3,5,100x100]
requestFocus() to MyComponent[,3,5,100x100]
requestFocus() to MyComponent[,3,5,100x100]
requestFocus() to MyComponent[,3,5,100x100]
requestFocus() to MyComponent[,3,5,100x100]
Exception in thread "AWT-Windows" java.lang.IllegalThreadStateException
        at java.lang.ThreadGroup.add(ThreadGroup.java:801)
        at java.lang.Thread.init(Thread.java:309)
        at java.lang.Thread.<init>(Thread.java:420)
        at java.awt.EventDispatchThread.<init>(EventDispatchThread.java:49)
        at java.awt.EventQueue$1.run(EventQueue.java:580)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.awt.EventQueue.initDispatchThread(EventQueue.java:577)
        at java.awt.EventQueue.wakeup(EventQueue.java:727)
        at sun.awt.SunToolkit.wakeupEventQueue(Native Method)
        at sun.awt.PostEventQueue.postEvent(SunToolkit.java:675)
        at sun.awt.SunToolkit.postEvent(SunToolkit.java:274)
        at sun.awt.windows.WComponentPeer.postEvent(WComponentPeer.java:529)
        at sun.awt.windows.WToolkit.eventLoop(Native Method)
        at sun.awt.windows.WToolkit.run(WToolkit.java:215)
        at java.lang.Thread.run(Thread.java:579)

2. JDK Version

I:\focus-no-return>java -version
java version "1.4.0-beta"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta-b60)
Java HotSpot(TM) Client VM (build 1.4.0-beta-b60, mixed mode)

3. PC configration

  OS : Windows NT 4.0 ( SP5 )
  MPU : Pentium II 400[MHz]
  Mem.: 256[MBytes]

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