--- a/jdk/src/share/classes/java/awt/Canvas.java	Thu Oct 14 18:59:15 2010 +0400
+++ b/jdk/src/share/classes/java/awt/Canvas.java	Thu Oct 14 18:56:18 2010 +0400
@@ -71,12 +71,13 @@
 
     @Override
     void setGraphicsConfiguration(GraphicsConfiguration gc) {
-        CanvasPeer peer = (CanvasPeer)getPeer();
-        if (peer != null) {
-            gc = peer.getAppropriateGraphicsConfiguration(gc);
+        synchronized(getTreeLock()) {
+            CanvasPeer peer = (CanvasPeer)getPeer();
+            if (peer != null) {
+                gc = peer.getAppropriateGraphicsConfiguration(gc);
+            }
+            super.setGraphicsConfiguration(gc);
         }
-
-        super.setGraphicsConfiguration(gc);
     }
 
     /**

--- a/jdk/src/windows/classes/sun/awt/windows/WWindowPeer.java	Thu Oct 14 18:59:15 2010 +0400
+++ b/jdk/src/windows/classes/sun/awt/windows/WWindowPeer.java	Thu Oct 14 18:56:18 2010 +0400
@@ -487,13 +487,8 @@
             newDev.addDisplayChangedListener(this);
         }
 
-        SunToolkit.executeOnEventHandlerThread((Component)target,
-                new Runnable() {
-                    public void run() {
-                        AWTAccessor.getComponentAccessor().
+        AWTAccessor.getComponentAccessor().
             setGraphicsConfiguration((Component)target, winGraphicsConfig);
-                    }
-                });
     }
 
     /**

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/Multiscreen/TranslucencyThrowsExceptionWhenFullScreen/TranslucencyThrowsExceptionWhenFullScreen.java	Thu Oct 14 18:56:18 2010 +0400
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2010, Oracle and/or its affiliates. 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+  @test
+  @bug 6838089
+  @summary Translucent windows should throw exception in FS mode
+  @author dmitry.cherepanov@oracle.com: area=awt-multiscreen
+  @run main TranslucencyThrowsExceptionWhenFullScreen
+*/
+
+import java.awt.*;
+import java.lang.reflect.InvocationTargetException;
+
+public class TranslucencyThrowsExceptionWhenFullScreen
+{
+    public static void main(String[] args)
+        throws InvocationTargetException, InterruptedException
+    {
+        EventQueue.invokeAndWait(
+            new Runnable(){
+                public void run() {
+                    Frame frame = new Frame();
+                    frame.setBounds(100,100,100,100);
+                    frame.setVisible(true);
+
+                    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
+                    GraphicsDevice[] devices = ge.getScreenDevices();
+                    for (GraphicsDevice device : devices) {
+                        testGraphicsDevice(device, frame);
+                    }
+
+                    frame.dispose();
+                }
+            }
+        );
+    }
+
+    private static void testGraphicsDevice(GraphicsDevice device, Frame frame) {
+        device.setFullScreenWindow(frame);
+        try {
+            frame.setOpacity(0.5f);
+            throw new RuntimeException("Test fails, there's no exception for device="+device);
+        } catch(IllegalComponentStateException e) {
+            device.setFullScreenWindow(null);
+        }
+    }
+}