amstafff, $req = mysql_query("SELECT * FROM `cms_sessions` WHERE `session_id` = '$session' LIMIT 1") or die("Invalid query: " . mysql_error());
посмотри ошибку
amstafff, $req = mysql_query("SELECT * FROM `cms_sessions` WHERE `session_id` = '$session' LIMIT 1") or die("Invalid query: " . mysql_error());
посмотри ошибку