It does work. If you do not believe me, check out a review below by another user, or visit the showplus demo site with IE9. Some versions of the MooTools script library shipped with older versions of the Joomla framework have trouble working in IE9, see the showplus FAQ for a proposed solution on how to get around this. (Alternatively, you should upgrade to the latest version of Joomla.) I am afraid the particular problem is outside the domain of showplus.