appVer = navigator.userAgent.toString().toLowerCase();

ns4 = (document.layers) ? true : false ;
ie4 = (document.all) ? true : false ;
mac = appVer.indexOf("mac") != -1;


function openWindow (sSrc, iWidth, iHeight, sCustom) {
	iHeight = Math.max (Number(iHeight), 100);
	iWidth = Math.max (Number(iWidth), 100);
	
	var iTop =  (screen.height - iHeight) * .5;
	var iLeft =  ((screen.height / 0.75) - iWidth ) * .5;
	
	sPosition = "left=" + iLeft + ",top=" + iTop + ",width=" + iWidth + ",height=" + iHeight ; 
	
	sCustom = sCustom == null ? "directories=0,location=0,menubar=0,resizable=0,scrollbars=0,status=0,toolbar=0," : sCustom ;
	
	window.open (sSrc, "_blank", sCustom + sPosition );
}