function loadCity(){
	//on récupère la valeur du select
	var depnum = $F('dep_list');
	
	//On charge les communes du département
	var req = new Ajax.Request('/xml/land-city-list.php', {
		method:"post", 
		postBody:"depnum="+depnum, 
		onSuccess:function(xhr){
			//console.log(xhr.responseText);
			//insertion dans le select des communes
			$('city_list').update(xhr.responseText);
		}
	});
	
	//On rend visible le select des communes
	$('city_p').setStyle({
		  display:'block'
		});
}

function initPage(){
	var depnum = $F('dep_list');
	if(depnum != 0){
		loadCity();
	}
	Event.observe($('dep_list'), 'change', loadCity);
}

Event.observe(window, 'load', initPage);