function slideSwitch(){
    var $active = $('#slideshow DIV.active1');

    if ($active.length == 0) $active = $('#slideshow DIV:last');
    var $next =  $active.next().length ? $active.next()
        : $('#slideshow DIV:first');
    $active.addClass('last-active');

    $next.css({opacity: 0.0})
        .addClass('active1')
        .animate({opacity: 1.0}, 900, function(){
            $active.removeClass('active1 last-active');
        });
}

$(function(){
    setInterval("slideSwitch()", 5000);
});