function communeChanged(e) {
	$E('div.progress').setStyle('display', 'block');

	$('UserZoneId').getParent('div.input').addClass('hidden');

	new Ajax('/ajax/zones_by_commune/' + $('UserCommuneId').value, {
		'method': 'get',
		'onComplete': zonesLoaded
	}).request();
}

function zonesLoaded(resp) {
	resp = Json.evaluate(resp);

	$E('div.progress').setStyle('display', 'none');

	var count = 0;
	var select = $('UserZoneId');
	select.setHTML('');

	for (value in resp) {
		select.adopt(new Element('option', {'value': value}).setText(resp[value]));
		count++;
	}

	if (count > 1) {
		select.getParent('div.input').removeClass('hidden');
	}
}