function fetch_object(idname)
{
        if (document.getElementById)
        {
                return document.getElementById(idname);
        }
        else if (document.all)
        {
                return document.all[idname];
        }
        else if (document.layers)
        {
                return document.layers[idname];
        }
        else
        {
                return null;
        }
}
function toggle_collapse(objid)
{
        obj = fetch_object(objid);
        button = fetch_object(objid + '_button');
        if (obj.style.display == 'none') {
                obj.style.display = '';
                button.src = 'hide.gif';
        } else {
                obj.style.display = 'none';
                button.src = 'show.gif';
        };
}