diff --git a/wp-admin/admin-header.php b/wp-admin/admin-header.php
index 95ead872f0..eecfe71e2e 100644
--- a/wp-admin/admin-header.php
+++ b/wp-admin/admin-header.php
@@ -6,7 +6,7 @@ if (!isset($_GET["page"])) require_once('admin.php'); ?>
 <html xmlns="http://www.w3.org/1999/xhtml">
 <head>
 <title><?php bloginfo('name') ?> &rsaquo; <?php echo $title; ?> &#8212; WordPress</title>
-<link rel="stylesheet" href="<?php echo get_settings('siteurl') ?>/wp-admin/wp-admin.css" type="text/css" />
+<link rel="stylesheet" href="<?php echo get_settings('siteurl') ?>/wp-admin/wp-admin.css?version=<?php bloginfo('version'); ?>" type="text/css" />
 <meta http-equiv="Content-Type" content="<?php bloginfo('html_type'); ?>; charset=<?php echo get_settings('blog_charset'); ?>" />
 
 <script type="text/javascript">
