Why does the page tree macro show the permalink and not the headline in confluence?

[Klaus IsbruchDN]

I use the page tree macro a lot, and recently found that for no apparent reason (at least for me :-)) some sub pages are shown with their headlines, and all new pages are displayed with the permalink string instead of the page's headline.

Funny though that the side bar shows the headline, always.

So, my question is, how do I tell the page tree macro, to list the headlines of the sub pages and not the permalink, which is not necessarily human readable.