function winopen(url,n,w,h,r)
{
	l = (window.screen.width-w)/2;
	t = (window.screen.height-h)/2;	
	window.open(url,n,'width='+w+',height='+h+',toolbar=no,menubar=no,scrollbars=yes,resizable='+r+',status=no,center=yes,left='+l+',top='+t);
}