http://www.onewaymule.org/onewayscripts/ is probably one of the best ones that I know of for the current version. The one you linked to is for a much older version of the forum.
Your welcome. While I've not worked with OneWayMule's Guest Book MOD myself (yet - I understand all to well about not having time), all the MODs I've used from him have been of exceedingly high quality. I don't think you'll be disappointed.