Index: modules/system/system-behavior.css
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system-behavior.css,v
retrieving revision 1.13
diff -u -p -r1.13 system-behavior.css
--- modules/system/system-behavior.css	9 Aug 2010 16:58:15 -0000	1.13
+++ modules/system/system-behavior.css	15 Sep 2010 14:23:40 -0000
@@ -313,3 +313,11 @@ html.js .js-hide {
   clip: rect(1px 1px 1px 1px); /* IE6, IE7 */
   clip: rect(1px, 1px, 1px, 1px);
 }
+/**
+ * Display link on focus.
+*/
+.element-invisible:active,
+.element-invisible:focus {
+  position: static !important;
+  clip: auto;
+}