function popUpWindow(url, popName, width, height, scroll, resizable){
	if( width == null || width == "" ) width = 600;
	if( height == null || height == "" ) height = 500;
	if( resizable == null || resizable == "" ) resizable = "yes";
	
	var left, top;
	top  = (window.screen.height - height) / 2;
	left = (window.screen.width  - width ) / 2;
	sFeatures = "width="+width+",height="+height+",left="+left+",top="+top+",resizable="+resizable;
	if(scroll == "yes") sFeatures += ",scrollbars=yes";
	else sFeatures += ",status=no,toolbar=no,menubar=no,location=no";

	var obj = window.open(url,popName,sFeatures);
	obj.focus();
	return obj;
}