Sorry for taking so long to reply.
Category:Ancient Greek terms needing attention is a hidden category, which shouldn't show up unless one's user preferences are set to "Show hidden categories". Tabbed languages is supposed to remove the original holding box for categories if the hidden categories aren't visible (and the non-hidden categories have all been sorted in to their sections), but leave the box there if the hidden categories are visible. Since the class name for visible hidden categories was changed during the upgrade to Mediawiki 1.19, the hidden categories weren't being identified as being visible ever. I've updated the script with the new class name, so this should be fixed now.