function required_field(field, errorField, errorMsg)
{
  with (field)
  {
    if (field.value.length == 0)
    {
      errorField.innerHTML = errorMsg;
      field.focus();
      return false;
    }

    errorField.innerHTML = "";
    return true;
  }
}

function validate_email( emailField, errorField, errorMsg )
{
  with (emailField)
  {
    emailpat = /^([a-zA-Z0-9])+([\.a-zA-Z0-9_-])*@([a-zA-Z0-9])+(\.[a-zA-Z0-9_-]+)+$/;
    if( !emailpat.test( emailField.value ) )
    {
      errorField.innerHTML = errorMsg;
      emailField.focus();
      emailField.select();
      return false;
    }

    errorField.innerHTML = "";
    return true;
  }
}