Problem with prev, next buttons in jcarousel

When customising a jcarousel component (link) I encountered a problem in IE6 (FF 3 was ok). I wanted to add my custom, smaller image buttons, but they were larger and inappriopate to the idea. It happend when button was enabled (disabled state was ok).


The only thing that was simple was to add more css code to classes that werent exposed in main component's library.
Here is the declaration(target image height was 9 pixels, but IE6 adds I think border height so I had to substract it to obtain 9 in total.)

.jcarousel-next, .jcarousel-prev{
    height:9px; line-height:7px; font-size:7px;
}

 Below are image buttons in jpg format. Due to ie6 doesn't display png files correctly - transparency. These are helpful only on white background.