Index: /CKEditor/trunk/CHANGES.html
===================================================================
--- /CKEditor/trunk/CHANGES.html	(revision 5391)
+++ /CKEditor/trunk/CHANGES.html	(revision 5392)
@@ -149,4 +149,6 @@
 		<li><a href="http://dev.fckeditor.net/ticket/5144">#5144</a> : [Chrome] Paste in webkit somtimes leaves extra 'div' element.</li>
 		<li><a href="http://dev.fckeditor.net/ticket/5021">#5021</a> : [Firefox] Typing in empty document start from second line in enterMode=BR.</li>
+		<li><a href="http://dev.fckeditor.net/ticket/5416">#5416</a> : [IE] Delete table throws a error when  CKEDITOR.enterMode = CKEDITOR.ENTER_BR.</li>
+		<li><a href="http://dev.fckeditor.net/ticket/4459">#4459</a> : [IE] Select element is penetrating the maximized editor in IE6.</li>
 		<li>Updated the following language files:<ul>
 			<li><a href="http://dev.fckeditor.net/ticket/5326">#5326</a> : Catalan;</li>
@@ -156,5 +158,4 @@
 			<li><a href="http://dev.fckeditor.net/ticket/5301">#5301</a> : Norwegian;</li>
 		</ul></li>
-		<li><a href="http://dev.fckeditor.net/ticket/5416">#5416</a> : [IE] Delete table throws a error when  CKEDITOR.enterMode = CKEDITOR.ENTER_BR.</li>
 	</ul>
 	<h3>
Index: /CKEditor/trunk/_source/plugins/maximize/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/maximize/plugin.js	(revision 5391)
+++ /CKEditor/trunk/_source/plugins/maximize/plugin.js	(revision 5392)
@@ -79,13 +79,4 @@
 	}
 
-	function getResizeHandler( mainWindow, editor )
-	{
-		return function()
-		{
-			var viewPaneSize = mainWindow.getViewPaneSize();
-			editor.resize( viewPaneSize.width, viewPaneSize.height, null, true );
-		};
-	}
-
 	function refreshCursor( editor )
 	{
@@ -104,4 +95,26 @@
 	}
 
+	/**
+	 * Adding an iframe shim to this element, OR removing the existing one if already applied.
+	 * Note: This will only affect IE version below 7.
+	 */
+	 function createIframeShim( element )
+	{
+		if ( !CKEDITOR.env.ie || CKEDITOR.env.version > 6 )
+			return;
+
+		var shim = CKEDITOR.dom.element.createFromHtml( '<iframe frameborder="0" tabindex="-1"' +
+					' src="javascript:' +
+					   'void((function(){' +
+						   'document.open();' +
+						   ( CKEDITOR.env.isCustomDomain() ? 'document.domain=\'' + this.getDocument().$.domain + '\';' : '' ) +
+						   'document.close();' +
+					   '})())"' +
+					' style="display:block;position:absolute;z-index:-1;' +
+					'progid:DXImageTransform.Microsoft.Alpha(opacity=0);' +
+					'"></iframe>' );
+		return element.append( shim, true );
+	}
+
 	CKEDITOR.plugins.add( 'maximize',
 	{
@@ -119,6 +132,13 @@
 			var outerScroll;
 
+			var shim;
+
 			// Saved resize handler function.
-			var resizeHandler = getResizeHandler( mainWindow, editor );
+			function resizeHandler()
+			{
+				var viewPaneSize = mainWindow.getViewPaneSize();
+				shim && shim.setStyles( { width : viewPaneSize.width + 'px', height : viewPaneSize.height + 'px' } );
+				editor.resize( viewPaneSize.width, viewPaneSize.height, null, true );
+			};
 
 			// Retain state after mode switches.
@@ -197,5 +217,7 @@
 									top : '0px'
 								} );
-							editor.resize( viewPaneSize.width, viewPaneSize.height, null, true );
+
+							shim =  createIframeShim( container );		// IE6 select element penetration when maximized. (#4459)
+							resizeHandler();
 
 							// Still not top left? Fix it. (Bug #174)
@@ -240,4 +262,10 @@
 							// Remove cke_maximized class.
 							container.removeClass( 'cke_maximized' );
+
+							if ( shim )
+							{
+								shim.remove();
+								shim = null;
+							}
 
 							// Emit a resize event, because this time the size is modified in