function checkAge(){
	 if (verifyAge(document.form1) ) {
		 with (document.form1) {
			mm=month.value;
			dd=day.value;
			yy=year.value;
			yy=parseInt(yy)+1900;
			bday=mm+'/'+dd+'/'+yy;
			bdate=new Date(bday);
			today=new Date();
			  
			age=howOld(dd,mm,yy);
			//alert(age)
			if((age >= 21) && (age <= 150)) {
				document.form1.submit();
			} else {
				document.location='under21.htm';
			}
		 }
	 }
}

function fixDate(date) {
  var base = new Date(0);
  var skew = base.getTime();
  if (skew > 0) { date.setTime(date.getTime() - skew); }
}

// determine age
function howOld(day,month,year) {
	var c = new Date(); // a new instance
	fixDate(c);

	var thisDay = c.getDate();
	var thisMonth = c.getMonth() + 1;
	var thisYear = c.getFullYear();

	var yearsold = thisYear - year; 
	var monthsold = 0;
	var daysold = 0;
	var age = '';

	if (thisMonth >= month) {
	  monthsold = thisMonth - month;
	}
	else {
	  yearsold--;
	  monthsold = thisMonth + 12 - month;
	}

	if (thisDay >= day) {
	 daysold = thisDay - day;
	}
	else {
		if (monthsold > 0) {
		  monthsold--;
		}
		else {
		  yearsold--;
		  monthsold += 11;
		}
		daysold = thisDay + 31 - day;
	}

	if (yearsold < 0) return '';

	if ((yearsold == 0) && (monthsold == 0) && (daysold == 0)) return '';

	if (yearsold > 0) {
		age = yearsold;
		if (yearsold > 1) age;
		age += ' ';
	}

	return age;
}

function autoTab(e) {
    if(this.value.length == this.getAttribute("maxlength") && 
        e.KeyCode != 8 && e.keyCode != 16 && e.keyCode != 9) {
            new Field.activate(findNextElement(this.getAttribute("tabindex")));
        }
}

function findNextElement(index) {
    elements = new Form.getElements('shippingInfo');
    for(i = 0; i < elements.length; i++) {
        element = elements[i];
        if(parseInt(element.getAttribute("tabindex")) == (parseInt(index) + 1)) {
            return element;
        }
    }
    return elements[0];
}