//##########################################
function checkForm(frm)
{
	var msg = "";
	
	if(frm.firstname.value == "")
		msg += "\n   Your first name     ";
	if(frm.lastname.value == "")
		msg += "\n   Your last name     ";	
	if(frm.email.value == "" || (!isEmail(frm.email.value)))
		msg += "\n   A valid email address";
	if(frm.telephone.value != "" &&  (!is_number(frm.telephone.value)))
		msg += "\n   A valid telephone number     ";
	
	if(msg != ""){
		alert("Please supply the following:     \n" + msg);
		return false;
	}else{
		return true;
	}
}

//####################  TELEPHONE FUNCTION  #########
function is_number(num)
{
	var supported = 0;
  if (window.RegExp) {
 		var r1 = new RegExp("[^0-9 \+]");
		return (!r1.test(num))
  }
}

//####################  EMAIL FUNCTION  ###############
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]{2,4}|[0-9]{1,4})(\\]?)$");
  return (!r1.test(str) && r2.test(str));
}