Index: src/wp-admin/css/admin-menu.css
===================================================================
--- src/wp-admin/css/admin-menu.css	(revision 49672)
+++ src/wp-admin/css/admin-menu.css	(working copy)
@@ -341,8 +341,6 @@
 
 #adminmenu .wp-menu-image img {
 	padding: 9px 0 0 0;
-	opacity: 0.6;
-	filter: alpha(opacity=60);
 }
 
 #adminmenu div.wp-menu-name {
@@ -472,12 +470,6 @@
 	border-right-color: #32373c;
 }
 
-#adminmenu li.menu-top:hover .wp-menu-image img,
-#adminmenu li.wp-has-current-submenu .wp-menu-image img {
-	opacity: 1;
-	filter: alpha(opacity=100);
-}
-
 #adminmenu li.wp-menu-separator {
 	height: 5px;
 	padding: 0;