function apply_model(form) 
{
  index = form.marques.value;
  if(index != "")
  {
    form.modeles.options.length = 0;
    form.modeles.options[form.modeles.options.length]=new Option('-- Selectionner --','');
    for (i=0;i<modeles[index].length;i++) 
    {
	    var o=new Option(modeles[index][i],modeles[index][i]);
	    form.modeles.options[form.modeles.options.length]=o;
    }
  }
}
function apply_categorie(form) 
{
  index = form.vehicule.value;
  form.categorie.options.length = 0;
  form.categorie.options[form.categorie.options.length]=new Option('-- Selectionner --','');
  for (propriete in categories[index]) 
  {
    if(categories[index][propriete].constructor == String) {
	    var o = new Option(categories[index][propriete], propriete);
	    form.categorie.options[form.categorie.options.length] = o;
	}
  }
}
function apply_tel(form) 
{
  prefixes = {lu:'+352', fr:'+33', be:'+32', de:'+49', nl:'+31', uk:'+44', ch:'+41', es:'+34', pt:'+351', it:'+39', cz:'+420', hu:'+36', pl:'+48', at:'+43'};
  index = form.pays.value;
  form.prefixe_tel1.value = prefixes[form.pays.value];
  form.prefixe_tel2.value = prefixes[form.pays.value];
  form.prefixe_gsm.value = prefixes[form.pays.value];
  form.prefixe_fax.value = prefixes[form.pays.value];
}