Request.UrlReferrer Problem

Hi,
? have flash in my aspx page and aspx page have flash in page.Flash call video.ashx and it returns xml.But when i used ie opera and chrome i can take the UrlReferrer but when i used firefox and safari  UrlReferrer coming null.How can i do ?

    public void ProcessRequest (HttpContext context) {
       
        string konser_refno = context.Request.UrlReferrer.ToString();
}
 
? am calling my flash abc.swf?cat_id=Request["cat_id"] and when i use like this i can return xml for my flash video gallery.Have another way to send Request in flash to my ashx and return xml?i try Session but i cant read session in my ashx ? Cookies is true way ?
 
Regars 
Ömer

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