Index: wp-admin/includes/class-wp-upgrader.php
===================================================================
--- wp-admin/includes/class-wp-upgrader.php	(revision 12223)
+++ wp-admin/includes/class-wp-upgrader.php	(working copy)
@@ -468,7 +468,7 @@
 		$i = 1;
 		foreach ( $plugins as $plugin ) {
 
-			$this->show_before = sprintf( '<h4>' . __('Updating plugin %d of %d...') . '</h4>', $i, $all );
+			$this->show_before = sprintf( '<h4>' . __('Updating plugin %1$d of %2$d...') . '</h4>', $i, $all );
 			$i++;
 
 			if ( !isset( $current->response[ $plugin ] ) ) {
