function popup(page,name,w,h,winstring)
{       
        var win=window.open(page,name,winstring + ',width=' + w + ',height=' + h);     
        if (navigator.appName == "Netscape")   
        {
        if (navigator.appVersion.indexOf('3')>=0)
        win.focus();
        if (navigator.appVersion.indexOf('3')<0)
        win.opener = self;      
       }
}