function vw_Open(bUrl,x,y,scroll)
{
	maxx=screen.width-12;
	maxy=screen.height-((document.all||document.layers||documentGetElementByID)?30:48);
	if (maxx<640-12) maxx=640-12;
	if (maxy<480-48) maxy=480-48;
	pos=""; w=x; h=y;
	if (w>maxx) { w=maxx; pos+="left=0,"; }
	if (h>maxy) { h=maxy; pos+="top=0,"; }
	var viewerpop=window.open(bUrl,'','location=no,toolbar=no,directories=no,menubar=no,status=no,resizable=no,scrollbars='+scroll+','+pos+'width='+w+',height='+h);
	if (!viewerpop.opener) viewerpop.opener=self;
	if (viewerpop.focus) viewerpop.focus();
}