function OpenDialogCentered(url, name, width, height, scrollbars) {
	var screenX = (screen.availWidth-width)/2;
	var screenY = (screen.availHeight-height)/2;
	var dlg = null;
	if (navigator.appName=="Netscape") {
		dlg = window.open(url, name,
			'status=no,scrollbars='+((scrollbars)?'yes':'no')+
			',screenX='+screenX+
			',screenY='+screenY+',width='+width+',height='+height);
	} else {
		dlg = window.open(url, name,
			'status=no,scrollbars='+((scrollbars)?'yes':'no')+
			',left='+screenX+
			',top='+screenY+',width='+width+',height='+height);
	}
	dlg.focus();
	return dlg;
}

function ShowModalPopup(sWindow,sName,sWidth,sHeight) {
   	if (navigator.appName == "Netscape") {
      	alert("Netscape is not yet supported.");
   	} else {
      	var sFeatures = "dialogHeight: " + sHeight + "px; dialogWidth: " + sWidth + "px;";
      	sFeatures = sFeatures + " dialogTop: px; dialogLeft: px; center: Yes; help: No;";
      	sFeatures = sFeatures + " resizable: No; status: No;";
      	return window.showModalDialog(sWindow,"",sFeatures);
   	}
}