function popup (href, width, height) {
	window.open(href,'popup','status=no,menubar=no,resizable=yes,width='+width+',height='+height);
	return false;
}

function isemail(str) {
  // are regular expressions supported?
  var supported = 0;
  if (window.RegExp) {
    var tempStr = "a";
    var tempReg = new RegExp(tempStr);
    if (tempReg.test(tempStr)) supported = 1;
  }
  if (!supported) 
    return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);
  var r1 = new RegExp("(@.*@)|(\\.\\.)|(@\\.)|(^\\.)");
  var r2 = new RegExp("^.+\\@(\\[?)[a-zA-Z0-9\\-\\.]+\\.([a-zA-Z]{2,3}|[0-9]{1,3})(\\]?)$");
  return (!r1.test(str) && r2.test(str));
}

function validate_sideform() {
	var form = document.frmemail;
	var canSubmit = true;

	if (form.chremail.value.length == 0) {
		alert('Please enter your email address');
		window.document.frmemail.chremail.focus();
		canSubmit = false;
	} else {
		if (isemail(form.chremail.value)==false) {
			alert('Please enter a valid email address');
			window.document.frmemail.chremail.focus();
			canSubmit = false;
		}
	}
	if (canSubmit) {
		form.submit();	
	}
}

var sideform_submit = document.getElementById("sideform_submit");
sideform_submit.onclick = function () {
	validate_sideform();
}