function checkform ( form )
{
  // see http://www.thesitewizard.com/archive/validation.shtml
  // for an explanation of this script and how to use it on your
  // own website

  // ** START **
  if (form.cf_field_2.value == "") {
    alert( "Please enter your first name." );
    form.cf_field_2.focus();
    return false ;
  }
    if (form.cf_field_3.value == "") {
    alert( "Please enter your last name." );
    form.cf_field_3.focus();
    return false ;
  }
    if (form.cf_field_4.value == "") {
    alert( "Please enter your email address." );
    form.cf_field_4.focus();
    return false ;
  }
    if (form.cf_field_9.value == "") {
    alert( "Please enter your phone number." );
    form.cf_field_9.focus();
    return false ;
  }

  // ** END **
  return true ;
}