В файле /includes/classes/vam_template.php меняйте:
require_once (DIR_FS_CATALOG.'includes/external/smarty/Smarty.class.php');
class vamTemplate extends Smarty {
на:
require_once (DIR_FS_CATALOG.'includes/external/smarty/SmartyBC.class.php');
class vamTemplate extends SmartyBC {
