var next, b, c = null;

function fireHeader() {
    b = $('background');
    c = b.getFirst('.activeslide');
    next = c.getNext() ? c.getNext() : c.getParent().getFirst('div');
    
    if (b.getFirst('.prevslide')) { b.getFirst('.prevslide').removeClass('prevslide'); }
    c.removeClass('activeslide').addClass('prevslide');
    next.set('tween', {duration:1000});
    next.setStyle('opacity', 0).addClass('activeslide').tween('opacity', 1);
}

window.addEvent('domready', function() {
    $$('a').each(function(a){
        if (a.getProperty('rel') == 'external') {
            a.setProperty('target', '_blank');
        }
    });
    
    if ($('background') && $('background').getElements('div').length > 1) {
        window.setInterval("fireHeader()", 5000);
    }
    
});