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.nomicognom.value == "") {
    alert( "Cal que posis el teu nom i cognoms." );
    form.nomicognom.focus();
    return false ;
  }
  if (form.email.value == "") {
    alert( "Cal que posis el teu mail." );
    form.email.focus();
    return false ;
  }

      if (form.fupload.value == "") {
    alert( "Cal que seleccionis un arxiu." );
    form.fupload.focus();
    return false ;
  }
  // ** END **
  return true ;
}