function &get_template_vars($name=null)
	{
		if(!isset($name)) {
			return $this->_tpl_vars;
		} elseif(isset($this->_tpl_vars[$name])) {
			return $this->_tpl_vars[$name];
		} else {
			// var non-existant, return valid reference
			$_tmp = null;
			return $_tmp;
		}
	}