JCarousel have recently changed (january 2011). It used to have a way to implement pause on hover with autoscroll.
With the new version I cannot solve how to
Updating the answer to stay current.
See https://github.com/jsor/jcarousel/issues/568 for the correct answer:
$('.jcarousel').hover(function() { $(this).jcarouselAutoscroll('stop'); }, function() { $(this).jcarouselAutoscroll('start'); });