function init () {
        var tabs = document.getElementsByClassName('tabs');
        for (var i = 0; i < tabs.length; i++) {
                $(tabs[i].id).onclick = function () {
                        getTabData(this.id);
                }
        }
}

function getTabData(id) {
        var url = 'inner_tab.php';
        var rand   = Math.random(9999);
        var pars   = 'id=' + id + 
                     'ID_elemento='+id_elemento+
		 	'&rand=' + rand;

        var myAjax = new Ajax.Request( url, {method: 'get', parameters: pars, onLoading: showLoad, onComplete: showResponse} );
}

function showLoad () {
        $('load').style.display = 'block';
}

function showResponse (originalRequest) {
        var newData = originalRequest.responseText;
        $('load').style.display = 'none';
        $('content').innerHTML = newData;
}