[themes] All page titles identical

[Agon S. Buchholz]

Progga wrote:

> If you are not shy about writing some PHP code, then you can call
> the debug_backtrace() function [0] from inside drupal_set_title() to
> find  out who is calling whom.

Thanks again. I tried to put this into 
./sites/all/modules/image/contrib/image_gallery/image_gallery.pages.inc:

   ...
     $breadcrumb[] = l($parent->name, 'image/tid/' . $parent->tid);
     }
     drupal_set_title(check_plain($gallery->name));
     drupal_set_message(print_r(debug_backtrace(), TRUE));
   }
   ...

However this didn't output anything but the normal page. What should I 
expect?

Greetings, -asb