function accordion(el) {
    if ($('visible') == el) {
        return;
    }
    var eldown = el.parentNode.id+'-body';
    if ($('visible')) {
        var elup = $('visible').parentNode.id+'-body';
        new Effect.Parallel(
        [
            new Effect.SlideUp(elup),
            new Effect.SlideDown(eldown)
        ], {
            duration: 0.3
        });
        $('visible').id = '';
    } else {
        new Effect.Parallel(
        [
            new Effect.SlideDown(eldown)
        ], {
            duration: 0.3
        });
	
    }
    el.id = 'visible';
    Cookie.set('visible', el.parentNode.id);  
}

function init() {
    // hide all elements apart from the one with id visible
    var acc = $('accordion');
    var apanels = acc.getElementsByTagName('div');
    var visible_panel = '';
    
    if (Cookie.get('visible')) {
	visible_panel = Cookie.get('visible');
    }
    
    for (i = 0; i < apanels.length; i++) {
        if (apanels[i].className == 'panel_body' && apanels[i].id != visible_panel + '-body') {
            apanels[i].style.display = 'none';
        }
    }

    $(visible_panel).firstDescendant().id = 'visible';
}

function addEvent(elm, evType, fn, useCapture) {
    elm["on"+evType]=fn;return;
}

addEvent(window, "load", init);