function validate() {
  if( $('firstName').value == "" ) {
    alert("Please enter your first name");
    $('firstName').focus();
    return false;
  } else if( $('lastName').value == "" ) {
    alert("Please enter your last name");
    $('lastName').focus();
    return false;
  } else if ($('emailAddr').value == "" ) {
    alert("Please enter your e-mail address");
    $('emailAddr').focus();
    return false;
  } else if (!filter.test($('emailAddr').value)){
    alert("Please enter one valid e-mail address");
    $('emailAddr').focus();
    return false;
  } else if ($('message').value == "" ) {
    alert("Please tell us what's on your mind");
    $('message').focus();
    return false;
  }
  return true;
}