function checkform ( form )
{
  // ** START **
  if (form.name.value == "") {
    alert( "Er is geen naam ingevuld..." );
    form.name.focus();
    return false ;
  }
  
  if (form.comments.value == "") {
    alert( "Er is geen bericht opgegeven..." );
    form.comments.focus();
    return false ;
  }
  // ** END **
  return true ;
}