Period in CSS Class for Paths

I have a path that a menu item uses with a period in it (e.g. http://drupal.org). The following code could name the class "menu-path-drupal.org". Shouldn't the period be removed?

I see this line:

$clean_path = str_replace(array('http://', '<', '>', '&', '=', '?', ':'), '', $menu_item['link']['href']);

Should '.' be added?