Problem with category_category_count_nodes()

If I'm correct, this should be replacement for taxonomy_term_count_nodes() function (that's how it is included inside taxonomy wrapper module).
However the original taxonomy function is build as recursive one, and counts all sub-terms. That should be, in my opinion, also a case with category_category_count_nodes(). Unfortunately present form doesn't count sub-categories but only direct descendants.
This is easy to notice using image_gallery module (part of image module packet), where image galleries which include sub-galleries show "0 images in this category".