<!-- SLIDESHOW-OPTIONS -->
function slideSwitch2() {
    var $active2 = $('#slideshow2 IMG.active2');

    if ( $active2.length == 0 ) $active2 = $('#slideshow2 IMG:last');

    var $next =  $active2.next().length ? $active2.next()
        : $('#slideshow2 IMG:first');

    $active2.addClass('last-active2');

    $next.css({opacity: 0.0})
        .addClass('active2')
        .animate({opacity: 1.0}, 2000, function() {
            $active2.removeClass('active2 last-active2');
        });
}

$(function() {
    setInterval( "slideSwitch2()", 5000 );
});
<!-- SLIDESHOW-OPTIONS END -->