popup refresh in IE problem

Hi!

my problem: I open a pop-up window and try to refresh it contents every
30 seconds.
the code below works in Firefox browser but in IE i get Permission
Denied error. any
suggestions how to make it work in IE?

Regards,
Grzegorz


<html>
<script>
var Mypopup;
var intervalHandler;


function odswiez() {
Mypopup.location.reload(true);
}


function funkcyjka () {
Mypopup = window.open('http://google.pl','okienko');
intervalHandler = setInterval("odswiez()",30000);

}


</script>

<body onload="funkcyjka()">
</body>
</html>

.