--- old/src/share/classes/java/awt/Window.java	2012-01-31 21:41:33.000000000 +0300
+++ new/src/share/classes/java/awt/Window.java	2012-01-31 21:41:33.000000000 +0300
@@ -3856,7 +3856,8 @@
             Graphics gg = g.create();
             try {
                 if (gg instanceof Graphics2D) {
-                    gg.setColor(getBackground());
+		    Color bgColor = ((SunToolkit)Toolkit.getDefaultToolkit()).getLayerBackground(this);
+                    gg.setColor(bgColor);
                     ((Graphics2D)gg).setComposite(AlphaComposite.getInstance(AlphaComposite.SRC));
                     gg.fillRect(0, 0, getWidth(), getHeight());
                 }
--- old/src/share/classes/sun/awt/SunToolkit.java	2012-01-31 21:41:34.000000000 +0300
+++ new/src/share/classes/sun/awt/SunToolkit.java	2012-01-31 21:41:34.000000000 +0300
@@ -2024,6 +2024,18 @@
     }
 
     /**
+     * Returns the background color of the window on X11 and Windows systems.
+     *
+     * On Mac platforms this method is overriden in LWCToolkit to return
+     * purely transparent color for non-opaque windows as we need to draw
+     * pure transparent pixel into a CALayer as the background color to
+     * implement translucent windows.
+     */
+    public Color getLayerBackground(Window w) {
+	return w.getBackground();
+    }
+
+    /**
      * Descendants of the SunToolkit should override and put their own logic here.
      */
     public int getNumberOfButtons(){
--- old/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java	2012-01-31 21:41:35.000000000 +0300
+++ new/src/macosx/classes/sun/lwawt/macosx/LWCToolkit.java	2012-01-31 21:41:35.000000000 +0300
@@ -720,6 +720,15 @@
     }
 
     @Override
+    public Color getLayerBackground(Window w) {
+	if (!w.isOpaque()) {
+	    return new Color(0f, 0f, 0f, 0f);
+	} else {
+	    return w.getBackground();
+	}
+    }
+
+    @Override
     public boolean enableInputMethodsForTextComponent() {
         return true;
     }
--- old/src/macosx/classes/sun/lwawt/LWWindowPeer.java	2012-01-31 21:41:36.000000000 +0300
+++ new/src/macosx/classes/sun/lwawt/LWWindowPeer.java	2012-01-31 21:41:36.000000000 +0300
@@ -1161,4 +1161,11 @@
     private boolean isGrabbing() {
         return this == grabbingWindow;
     }
+    
+    @Override
+    public void setBackground(final Color c) {
+        // draw pure transparent pixels into the CALayer as the background color
+        Color bgColor = ((SunToolkit)Toolkit.getDefaultToolkit()).getLayerBackground(getTarget());
+        super.setBackground(bgColor);
+    }
 }
--- old/src/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java	2012-01-31 21:41:37.000000000 +0300
+++ new/src/macosx/classes/sun/lwawt/macosx/CPlatformWindow.java	2012-01-31 21:41:37.000000000 +0300
@@ -604,8 +604,9 @@
     public void setOpaque(boolean isOpaque) {
         CWrapper.NSWindow.setOpaque(getNSWindowPtr(), isOpaque);
         if (!isOpaque) {
-            long clearColor = CWrapper.NSColor.clearColor();
-            CWrapper.NSWindow.setBackgroundColor(getNSWindowPtr(), clearColor);
+            float[] bgValues = target.getBackground().getComponents(null);
+            CWrapper.NSWindow.setBackgroundColor(getNSWindowPtr(),
+                          bgValues[0], bgValues[1], bgValues[2], bgValues[3]);
         }
     }
 
--- old/src/macosx/classes/sun/lwawt/macosx/CWrapper.java	2012-01-31 21:41:38.000000000 +0300
+++ new/src/macosx/classes/sun/lwawt/macosx/CWrapper.java	2012-01-31 21:41:38.000000000 +0300
@@ -63,7 +63,8 @@
 
         public static native void setAlphaValue(long window, float alpha);
         public static native void setOpaque(long window, boolean opaque);
-        public static native void setBackgroundColor(long window, long color);
+        public static native void setBackgroundColor(long window, float red, float green,
+                                                     float blue, float alpha);
 
         public static native void miniaturize(long window);
         public static native void deminiaturize(long window);
@@ -95,8 +96,4 @@
         public static native Rectangle2D visibleFrame(long screen);
         public static native long screenByDisplayId(int displayID);
     }
-
-    public static final class NSColor {
-        public static native long clearColor();
-    }
 }
--- old/src/macosx/native/sun/awt/CWrapper.m	2012-01-31 21:41:39.000000000 +0300
+++ new/src/macosx/native/sun/awt/CWrapper.m	2012-01-31 21:41:39.000000000 +0300
@@ -359,17 +359,21 @@
 /*
  * Class:     sun_lwawt_macosx_CWrapper$NSWindow
  * Method:    setBackgroundColor
- * Signature: (J)V
+ * Signature: (JFFFF)V
  */
 JNIEXPORT void JNICALL
 Java_sun_lwawt_macosx_CWrapper_00024NSWindow_setBackgroundColor
-(JNIEnv *env, jclass cls, jlong windowPtr, jlong colorPtr)
+(JNIEnv *env, jclass cls, jlong windowPtr,
+ jfloat red, jfloat green, jfloat blue, jfloat alpha)
 {
 JNF_COCOA_ENTER(env);
 
     AWTWindow *window = (AWTWindow *)jlong_to_ptr(windowPtr);
-    NSColor *color = (NSColor *)jlong_to_ptr(colorPtr);
     [JNFRunLoop performOnMainThreadWaiting:NO withBlock:^(){
+        NSColor *color = [NSColor colorWithCalibratedRed:(CGFloat)red
+                                                   green:(CGFloat)green
+                                                    blue:(CGFloat)blue
+                                                   alpha:(CGFloat)alpha];
         [window setBackgroundColor:color];
     }];
 
@@ -714,26 +718,3 @@
 
     return screenPtr;
 }
-
-/*
- * Class:     sun_lwawt_macosx_CWrapper$NSColor
- * Method:    clearColor
- * Signature: ()J
- */
-JNIEXPORT jlong JNICALL
-Java_sun_lwawt_macosx_CWrapper_00024NSColor_clearColor
-(JNIEnv *env, jclass cls)
-{
-    __block jlong clearColorPtr = 0L;
-
-JNF_COCOA_ENTER(env);
-
-    [JNFRunLoop performOnMainThreadWaiting:YES withBlock:^(){
-        clearColorPtr = ptr_to_jlong([NSColor clearColor]);
-    }];
-
-JNF_COCOA_EXIT(env);
-
-    return clearColorPtr;
-}
-