function checkActieForm( form ) {
  if (form.naam.value == "") {
    alert( "Please fill in your first name." );
    form.naam.focus();
    return false ;
  }

  if (form.achternaam.value == "") {
    alert( "Please fill in your last name." );
    form.achternaam.focus(); 
    return false ;
  }
  if (form.adres.value == "") {
    alert( "Please fill in your address." );
    form.adres.focus(); 
    return false ;
  }
  if (form.postcode.value == "") {
    alert( "Please fill in your postal code." );
    form.postcode.focus();
    return false ;
  }
  /*var postcode = form.postcode.value;
  valid = new RegExp("^[0-9]{4}[a-zA-Z]{2}$").exec(postcode);
  if(!valid) { 
    alert( "The postal code you have entered is invalid.\n bv. 1000AA " );
    form.postcode.focus();
    return false;
  }*/
  if (form.plaats.value == "") {
    alert( "Please fill in your city." );
    form.plaats.focus();
    return false ;
  }
	if (form.land.value == "") {
    alert( "Please fill in your country." );
    form.land.focus();
    return false ;
  }
  /*if (form.tel.value != "") {
   var tel = form.tel.value;
   valid = new RegExp("^[0-9]{10}$").exec(tel);
   if(!valid) { 
     alert( "Het door uw ingevoerder telefoon nummer is ongeldig.\nbv. 0206666666" );
     form.tel.focus();
     return false;
   }
  }*/

	if (form.email.value == "") {
    alert( "Please fill in your e-mail address." );
    form.email.focus();
    return false ;
  }
  var emailAdres = form.email.value;
  valid = new RegExp("^[a-zA-Z]+([.]?[a-zA-Z0-9_-]+)*[@]([a-zA-Z0-9_-]+[.])+([a-zA-Z]{2,4})$").exec(emailAdres);
  if(!valid) { 
    alert( "The e-mail address you have entered is invalid." );
    form.email.focus();
    return false;
  }

  return true;
 }