[support] username.tpl.php and user_list.tpl.php

Default 4.7.2 installation. I want to change "Who's online" layout. So, added overwrites to template.tpl.php <?php function phptemplate_user_list($items, $title = NULL) { return _phptemplate_callback('user_list', array('items' => $items, 'title' => $title)); }

function phptemplate_username($object) { /*if ($object->in_preview) { return theme_username($object); }*/ return _phptemplate_callback('username', array('object' => $object)); } ?>

and two files username.tpl.php and user_list.tpl.php with what i want to current thmplate directory. Reloaded phpthemplate engine by accessing /admin/themes and reload it, but nothing changed. "Who's online" looks exactly the same. What can be a problem?