Problems with jCarousel

Question

I'm trying to modify jcarousel by displaying 5 items at once and moving 4 at a time, however, implementing the following code:

$('#mycarousel').jcarousel({
    scroll: 4
});

still only moves 3 items at a time.

This works:

$('#mycarousel').jcarousel({
    scroll: 1
});

by moving only 1 item, but once I go past 3, it doesn't move any more.

Any ideas?