--- a/jdk/src/windows/classes/sun/awt/windows/WPanelPeer.java	Mon Mar 24 18:24:15 2008 +0300
+++ b/jdk/src/windows/classes/sun/awt/windows/WPanelPeer.java	Tue Mar 25 16:23:09 2008 +0300
@@ -30,9 +30,11 @@
 import java.util.Vector;
 
 import sun.awt.SunGraphicsCallback;
+import java.util.logging.*;
 
 class WPanelPeer extends WCanvasPeer implements PanelPeer {
 
+    private static final Logger log = Logger.getLogger("sun.awt.windows.WPanelPeer");
     // ComponentPeer overrides
 
     public void paint(Graphics g) {
@@ -131,8 +133,16 @@
         for (int i = 0; i < cont.getComponentCount(); i++) {
             Component comp = cont.getComponent(i);
             if (!comp.isLightweight()) {
-                if (comp.getPeer() != null) {
-                    peers.add(comp.getPeer());
+                ComponentPeer peer = comp.getPeer();
+                if (peer != null && (peer instanceof WComponentPeer))
+                {
+                    peers.add(peer);
+                } else {
+                    if (log.isLoggable(Level.FINE)) {
+                        log.log(Level.FINE,
+                                "peer of a {0} is null or not a WComponentPeer: {1}.",
+                                new Object[]{comp, peer});
+                    }
                 }
             }
             if (comp.isLightweight() && comp instanceof Container) {

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/Component/isLightweightCrash/IsLightweightCrash.java	Tue Mar 25 16:23:09 2008 +0300
@@ -0,0 +1,59 @@
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+  @test
+  @bug 6255653
+  @summary REGRESSION: Override isLightweight() causes access violation in awt.dll
+  @author Andrei Dmitriev: area=awt-component
+  @run main IsLightweightCrash
+*/
+
+/*
+ * The test may not crash for several times so iteratively continue up to some limit.
+ */
+
+import java.awt.*;
+
+public class IsLightweightCrash {
+    public static int ITERATIONS = 20;
+
+    public static void main(String []s)
+    {
+        for (int i = 0; i < ITERATIONS; i++){
+            showFrame(i);
+        }
+    }
+
+    private static void showFrame(int i){
+        System.out.println("iteration = "+i);
+        Frame f = new Frame();
+        f.add(new AHeavyweightComponent());
+        f.setVisible(true);
+        f.setVisible(false);
+    }
+}
+
+class AHeavyweightComponent extends Component {
+    public boolean isLightweight() { return false; }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/Component/isLightweightCrash/StubPeerCrash.java	Tue Mar 25 16:23:09 2008 +0300
@@ -0,0 +1,188 @@
+/*
+ * Copyright 2007 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+  @test
+  @bug 6255653
+  @summary REGRESSION: Override isLightweight() causes access violation in awt.dll
+  @author Andrei Dmitriev: area=awt-component
+  @run main StubPeerCrash
+*/
+
+/*
+ * The test may not crash for several times so iteratively continue up to some limit.
+ */
+
+import java.awt.*;
+import java.awt.peer.*;
+import java.awt.event.PaintEvent;
+import java.awt.image.ImageProducer;
+import java.awt.image.ImageObserver;
+import java.awt.image.ColorModel;
+import java.awt.image.VolatileImage;
+import java.awt.GraphicsConfiguration;
+import sun.awt.CausedFocusEvent;
+import sun.java2d.pipe.Region;
+
+public class StubPeerCrash {
+    public static int ITERATIONS = 20;
+
+    public static void main(String []s)
+    {
+        for (int i = 0; i < ITERATIONS; i++){
+            showFrame(i);
+        }
+    }
+
+    private static void showFrame(int i){
+        System.out.println("iteration = "+i);
+        Frame f = new Frame();
+        f.add(new AHeavyweightComponent());
+        f.setVisible(true);
+        f.setVisible(false);
+    }
+}
+
+class AHeavyweightComponent extends Component {
+    private ComponentPeer peer = new StubComponentPeer();
+
+    public AHeavyweightComponent(){
+    }
+
+    public boolean isLightweight() {
+        return false;
+    }
+
+    public ComponentPeer getPeer(){
+        return peer;
+    }
+}
+
+class StubComponentPeer implements ComponentPeer {
+    public boolean isObscured(){return true;};
+    public boolean canDetermineObscurity(){return true;};
+    public void                setVisible(boolean b){};
+    public void                setEnabled(boolean b){};
+    public void                paint(Graphics g){};
+    public void                repaint(long tm, int x, int y, int width, int height){};
+    public void                print(Graphics g){};
+    public void                setBounds(int x, int y, int width, int height, int op){};
+    public void                handleEvent(AWTEvent e){};
+    public void                coalescePaintEvent(PaintEvent e){};
+    public Point               getLocationOnScreen(){return null;};
+    public Dimension           getPreferredSize(){return null;};
+    public Dimension           getMinimumSize(){return null;};
+    public ColorModel          getColorModel(){return null;};
+    public Toolkit             getToolkit(){return null;};
+    public Graphics            getGraphics(){return null;};
+    public FontMetrics         getFontMetrics(Font font){return null;};
+    public void                dispose(){};
+    public void                setForeground(Color c){};
+    public void                setBackground(Color c){};
+    public void                setFont(Font f){};
+    public void                updateCursorImmediately(){};
+    public boolean             requestFocus(Component lightweightChild,
+                                     boolean temporary,
+                                     boolean focusedWindowChangeAllowed,
+                                     long time, CausedFocusEvent.Cause cause){
+        return true;
+    };
+    public boolean             isFocusable(){return true;};
+
+    public Image               createImage(ImageProducer producer){return null;};
+    public Image               createImage(int width, int height){return null;};
+    public VolatileImage       createVolatileImage(int width, int height){return null;};
+    public boolean             prepareImage(Image img, int w, int h, ImageObserver o){return true;};
+    public int                 checkImage(Image img, int w, int h, ImageObserver o){return 0;};
+    public GraphicsConfiguration getGraphicsConfiguration(){return null;};
+    public boolean     handlesWheelScrolling(){return true;};
+    public void createBuffers(int numBuffers, BufferCapabilities caps) throws AWTException{};
+    public Image getBackBuffer(){return null;};
+    public void flip(BufferCapabilities.FlipContents flipAction){};
+    public void destroyBuffers(){};
+
+    /**
+     * Reparents this peer to the new parent referenced by <code>newContainer</code> peer
+     * Implementation depends on toolkit and container.
+     * @param newContainer peer of the new parent container
+     * @since 1.5
+     */
+    public void reparent(ContainerPeer newContainer){};
+    /**
+     * Returns whether this peer supports reparenting to another parent withour destroying the peer
+     * @return true if appropriate reparent is supported, false otherwise
+     * @since 1.5
+     */
+    public boolean isReparentSupported(){return true;};
+
+    /**
+     * Used by lightweight implementations to tell a ComponentPeer to layout
+     * its sub-elements.  For instance, a lightweight Checkbox needs to layout
+     * the box, as well as the text label.
+     */
+    public void        layout(){};
+
+
+     public    Rectangle getBounds(){return null;};
+
+    /**
+     * Applies the shape to the native component window.
+     * @since 1.7
+     */
+    public void applyShape(Region shape){};
+
+    /**
+     * DEPRECATED:  Replaced by getPreferredSize().
+     */
+    public Dimension           preferredSize(){return null;};
+
+    /**
+     * DEPRECATED:  Replaced by getMinimumSize().
+     */
+    public Dimension           minimumSize(){return null;};
+
+    /**
+     * DEPRECATED:  Replaced by setVisible(boolean).
+     */
+    public void                show(){};
+
+    /**
+     * DEPRECATED:  Replaced by setVisible(boolean).
+     */
+    public void                hide(){};
+
+    /**
+     * DEPRECATED:  Replaced by setEnabled(boolean).
+     */
+    public void                enable(){};
+
+    /**
+     * DEPRECATED:  Replaced by setEnabled(boolean).
+     */
+    public void                disable(){};
+
+    /**
+     * DEPRECATED:  Replaced by setBounds(int, int, int, int).
+     */
+    public void                reshape(int x, int y, int width, int height){};
+}