[Stoebi]

Hope, that helps, code is from a friend of mine (Surviver):

    <script type="text/javascript">
    <!--
        function toggle_p_collapse(objid, un)
        {
            obj = fetch_object('collapseobj_' + objid);
            img = fetch_object('collapseimg_' + objid);
            cel = fetch_object('collapsecel_' + objid);

            if (!obj)
            {
                return false;
            }

            if (un)
            {
                obj.style.display = '';
                save_collapsed(objid, false);

                if (img)
                {
                    img_re = new RegExp("_collapsed\\.gif$");
                    img.src = img.src.replace(img_re, '.gif');
                }

                if (cel)
                {
                    cel_re = new RegExp("^(thead|tcat)(_collapsed)$");
                    cel.className = cel.className.replace(cel_re, '$1');
                }
            }
            else
            {
                obj.style.display = 'none';
                save_collapsed(objid, true);

                if (img)
                {
                    img_re = new RegExp("_alt\\.gif$");
                    img.src = img.src.replace(img_re, '_alt_collapsed.gif');
                }

                if (cel)
                {
                    cel_re = new RegExp("^(thead|tcat)$");
                    cel.className = cel.className.replace(cel_re, '$1_alt_collapsed');
                }
            }
                return false;
        }

        function collapse_all(un)
        {
            if (un)
            {
                for (var i in products)
                {
                    toggle_p_collapse(products[i], true);
                }
            }
            else
            {
                for (var i in products)
            {
                toggle_p_collapse(products[i], false);
            }
        }
            return false;
    }
    //-->
    </script>