[jQuery] CSS problem with slideDown() in IE6

[jQuery] CSS problem with slideDown() in IE6

Hi all!
I'm experiencing a weird behavior in IE6 when I use slideDown().
An example can be seen @ <a href="http://www.bookevent.dk/CayesWeb/">www.bookevent.dk/CayesWeb/</a>  click on a li element in the menu (click on the first nested li, "BAGMAN" if you loose the picture).
When an ul element slideDown my <div id="display"> slides down as well. I have tested with FF2, IE7, Safari3 and Opera 9.22 without seeing that side effect. Opera 9.22 does display a small hiccup when you click a li the first time.
I am by no means a CSS guru but I do know a little something. But I don't know how to overcome this issue. Maybe someone can tell me how jQuery works when slide*() is used?
Thanks in advance!!
Cheers, Jon!