function autoScroller(contentDiv, speed)
{
    contentDiv = "#"+contentDiv;
    var scrollSpeed = (speed==null) ? 5 : parseInt(speed);
    
    // double make sure the autoScroller-container has the correct css position and overflow property
    $(contentDiv).parent().css({position:'relative',overflow:'hidden'});
    
    // set contentDiv style
    $(contentDiv).css({position:'absolute',top:0});
    // get contentDiv height
    contentDivHeight = $(contentDiv).height();

    // call periodical
    var lastUpdate = new Date();
    $(contentDiv).everyTime(100, function(i) {

        var currentTime = new Date();
        var diff = currentTime - lastUpdate;
        if (scrollSpeed * diff / 1000 < 1 && scrollSpeed != 0)
        {
            return;
        }
        lastUpdate = currentTime;

        if (parseInt($(this).css('top')) > (contentDivHeight * (-1) + 8)) {
            // move scroller upwards
            offset = parseInt($(this).css('top')) - (scrollSpeed * diff / 1000) + "px";
            $(this).css({ 'top': offset });
        }
        // reset to original position
        else {
            // reset to original position
            offset = parseInt($(this).parent().height()) + 8 + "px";
            $(this).css({ 'top': offset });
        }
    });
    
    // on mouse over event, pause the scroller
    $(contentDiv).mouseover(function ()
    {
        speed = scrollSpeed;
        scrollSpeed = 0;       
    });
    
    // on mouse out event, start the scroller
    $(contentDiv).mouseout(function ()
    {
        scrollSpeed = speed;
    });
}