Always highest resolution with rrdcached

Hi,

I'm using RRDCached with PHP rrdtool (1.4.99910112300) binding.
When I try fetch data from rrdcached (with rrdtool v 1.4.3) from
remote server with command like this:

            $res = 600;
            $opt = array();
            $opt[] = "--start";
            $opt[] = (int)(($this->end - $this->epoch) / $res) * $res;
            $opt[] = "--end";
            $opt[] = (int)($this->end / $res) * $res;
            $opt[] = "--resolution";
            $opt[] = $res;
            $opt[] = "--daemon";
            $opt[] = 'host:port';
            $opt[] = $cfs[$y];

            $ret = rrd_fetch($rrds[$y], $opt, count($opt));

I get always highest resolution (10). When I try fetch data direct
from files with command line it works fine.
Can You give me some advise?

When I run HELP for FETCH command from rrdcached I get this:
Usage: FETCH <file> <CF> [<start> [<end>]]
There is no resolution parameter?

Thank you for every response.

Best regards

Marek Fiala
www.bijk.com