var newwindow;
function popup(url)
{
	if (newwindow && !newwindow.closed)
		{
			newwindow.focus();
		} 
	else 
		{
			newwindow=window.open(url,'name','height=420,width=600,left=200,top=200,resizable=false,scrollbars=true,toolbar=no,status=yes');
			if (window.focus)
			{
				newwindow.focus()
			}
		}
}

function tidy() {
	if (newwindow.location && !newwindow.closed) { 
   		newwindow.close(); } 
}