Index: /CKEditor/trunk/_source/plugins/panel/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/panel/plugin.js	(revision 4196)
+++ /CKEditor/trunk/_source/plugins/panel/plugin.js	(revision 4197)
@@ -256,6 +256,5 @@
 
 		// Disable context menu for panels.
-		if ( CKEDITOR.plugins.contextMenu )
-			CKEDITOR.plugins.contextMenu.prototype.addDisabledTarget( this.element );
+		this.element.disableContextMenu();
 	},