function openwin(pageurl,winname,wd,hg,rsize,scrollb) {
	//var osx = event.clientX-200;
	//var osy = event.clientY-25;
	//if (center == "yes") {
		var osx = (screen.width - wd) / 2;
		var osy = (screen.height - hg) / 2;
	//}
	var atrs = "width=" + wd + ",height=" + hg + ",resizable=" + rsize + ",scrollbars=" + scrollb + ",toolbar=no,location=no,directories=no,status=no,menubar=no,";
	atrs = atrs + "screenX=100,screenY=100,left=" + osx + ",top=" + osy;
	var winObj = window.open(pageurl,winname,atrs);
}

function checkDigits(fieldname) {
       var digit = "0123456789";
       for (var oi = 0; oi < fieldname.value.length; oi++) {
       var onechar=fieldname.value.substr(oi,1);
               if (digit.indexOf(onechar) == -1) {
                       alert('You can use only numbers in this field');
                       fieldname.focus();
                       return;
               }
       }
}