ftp_base::rename

	function rename($from, $to) {
		if(!$this->_exec("RNFR ".$from, "rename")) return FALSE;
		if(!$this->_checkCode()) return FALSE;
		if($this->_code==350) {
			if(!$this->_exec("RNTO ".$to, "rename")) return FALSE;
			if(!$this->_checkCode()) return FALSE;
		} else return FALSE;
		return TRUE;
	}