function getCities(){

	var pars = "depto=" + $F('depto');
	new Ajax.Request('ajax/get_cities.php', {
		method: 'post',
		parameters: pars,
		onSuccess: function(transport) {
			$('cities').update(transport.responseText);
		}
	});
}

function getAgencies(){

	var pars = "city=" + $F('city');
	new Ajax.Request('ajax/get_agencies.php', {
		method: 'post',
		parameters: pars,
		onSuccess: function(transport) {
			$('agencies').update(transport.responseText);
		}
	});
}