function popupWindow(url,width,height,toolbar,location,status,menubar,scrollbars)
{
var options = 'toolbar='+toolbar+',location='+location+',status='+status+',menubar='+menubar+',scrollbars='+scrollbars+',resizable=yes';
if(width > 0 && height > 0)
{
var centered;
x = (screen.availWidth - width) / 2;
y = (screen.availHeight - height) / 2;
centered ='width=' + width + ',height=' + height + ',left=' + x + ',top=' + y + ',' + options;
}else
{
centered = options;
}	
var popup = window.open(url, '_blank', centered);
if (!popup.opener) popup.opener = self;
popup.focus();
}