Book page not linking to all child nodes

While exploring book.module for use as an FAQ manager, I've unearthed a problem with the book overview page. You can easily see the problem by reviewing my 3 page book at http://demo.drupal.org/admin.php?mod=book&op=view&id=4 (sign in with your www.drop.org username if necessary). Now click on the top page of the book entitled 'MW Demo Book' (http://demo.drupal.org/node.php?id=4). This is the broken page - only 1 child link is displayed. But the prior page told you that 2 child nodes should be dislayed. The missing node is not a book page. It is a blog entry. I suspect that book gets confused when its pages are nodes instead of book pages (not sure about this conclusion). You can see that the 'missing node' *is* properly recognized drill down into the book - http://demo.drupal.org/node.php?id=5. The 'missing node' is now properly hyperlinked under 'next'.

I'm hopeful that someone more familiar with the guts of book can squash this bug. The bug is easily repeatable on your development instance by adding a node to the book which is *not* a book page.

-moshe