function validateForm() { //v4.0

  var errors='';
  var phoneFilter = /^\d{3}$/;
  var phoneFilter2 = /^\d{4}$/;
  var emailFilter = /^[\w\.-]*[a-zA-Z0-9_]@[\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$/;
  //var emailFilter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
  var poboxFilter = /^([Pp]\.{0,1}[Oo]\.{0,1} *[Bb][Oo][Xx] *\d{1,5})/;
  
  if (document.forms["leadForm"].firstName.value == "") {
  	errors += '- First name is required\n';
  }
  if (document.forms["leadForm"].lastName.value == "") {
  	errors += '- Last name is required\n';
  }
  if (document.forms["leadForm"].emailAddress.value == "") {
    	errors += '- Email Address is required\n';
    } else {
  	  if (!emailFilter.test(document.forms["leadForm"].emailAddress.value))
  		  errors += '- Invalid email address. Examples: abc@xyz.com .\n';
  }

  if(!phoneFilter.test(document.forms["leadForm"].phone1.value)
        || !phoneFilter.test(document.forms["leadForm"].phone2.value)
        || !phoneFilter2.test(document.forms["leadForm"].phone3.value)) {
        errors += '- Phone number is required .\n';
    }

  if (errors) alert('The following error(s) occurred:\n'+errors);
  document.MM_returnValue = (errors == '');
}

function numbersOnly(evt) {
    evt = (evt) ? evt : event;
    var charCode = (evt.charCode) ? evt.charCode : ((evt.keyCode) ? evt.keyCode :
        ((evt.which) ? evt.which : 0));
    if (charCode > 31 && (charCode < 48 || charCode > 57)) {
        return false;

    }
    return true;
}


function lettersOnly(evt) {
    evt = (evt) ? evt : event;
    var charCode = (evt.charCode) ? evt.charCode : ((evt.keyCode) ? evt.keyCode :
        ((evt.which) ? evt.which : 0));
    if (charCode > 31 && (charCode!= 45) && (charCode!= 32) &&(charCode < 65 || charCode > 90) &&
        (charCode < 97 || (charCode > 122))) {
        return false;
    }
    return true;
}