Index: wp-admin/includes/menu.php
===================================================================
--- wp-admin/includes/menu.php	(revision 18984)
+++ wp-admin/includes/menu.php	(working copy)
@@ -215,7 +215,8 @@
 }
 
 // Remove the last menu item if it is a separator.
-$last_menu_key = array_pop( array_keys( $menu ) );
+$array_keys = array_keys( $menu );
+$last_menu_key = array_pop( $array_keys );
 if ( !empty( $menu ) && 'wp-menu-separator' == $menu[ $last_menu_key ][ 4 ] )
 	unset( $menu[ $last_menu_key ] );
 unset( $last_menu_key );
