if (document.getElementById && document.createTextNode) {
  addEvent(window, "load", initForm);
}

function initForm() {
 if (document.forms["booking"]) {
    //set custom validation rules
    document.forms["booking"]["confirmation"][0].validationRules.push(JLTA.Validation.rule.custom);
    document.forms["booking"]["confirmation"][0].customRules = function() {
      if (!(this.valid = this.form["confirmation"][0].checked)) {
        this.form.valid = false;
        this.error = "Please read PDS, FSG and Terms and Conditions of use before proceeding.";
      }
    }
  }
}