variables problem

I am sending data from get method:

http://127.0.0.6/coord.php?xdata=35&ydata=150

Making cookie:

<?
if((IsSet($xdata))AND(IsSet($xdata))){
setcookie("x",$xdata);
setcookie("y",$ydata);
}
?>

I send info of the cookie with JS to Flash(my object is FlashCoord):

<script language=javascript type="text/javascript">

thisCookie=document.cookie.split("; ");
xdata=thisCookie[0].split("=")[1];
ydata=thisCookie[1].split("=")[1];
document.FlashCoord.SetVariable("xdata", xdata);
document.FlashCoord.SetVariable("ydata", ydata);
document.write("X:"+xdata+"<br>");
document.write("Y:"+ydata);

</SCRIPT>

In FLASH:

var xdata;
var ydata;
with (aaa) {
aaa._x = xdata;
aaa._y = ydata;
if (xdata==null) {
aaa._x = 0;
aaa._y = 0;
}
}

But I have this problem: It works only in the first time. When I reload movie variables into FLASH are null although variables in cookies are OK?

If I open new window it works again but again only for the first time.

Please help

Thank you