function stamp() {
		if (!$this->sid)
			session_start();
		return $this->_cache->exists($this->sid.'.@',$data)?
			$data['stamp']:FALSE;
	}
function stamp() {
		if (!$this->sid)
			session_start();
		return $this->_cache->exists($this->sid.'.@',$data)?
			$data['stamp']:FALSE;
	}
function stamp ( ) { if ( ! $ this -> sid ) session_start ( ) ; return $ this -> _cache -> exists ( $ this -> sid . '.@' , $ data ) ? $ data [ 'stamp' ] : FALSE ; }
Return Unix timestamp
@return string|FALSE
Return Unix timestamp