function textCounter( field, countfield, maxlimit ) {
  if ( field.value.length > maxlimit )
  {
    field.value = field.value.substring( 0, maxlimit );
    alert( 'Uw tekst mag niet meer dan 255 tekens bevatten.' );
    return false;
  }
  else
  {
    countfield.value = maxlimit - field.value.length;
  }
}