With the latest bazaar pull (revno 99388), after `make bootstrap' (macosx 10.6.2, configure --with-ns), the resulting emacs gives me an error when I try to open an existing file in org-mode.  The backtrace contains a null character, so I'm attaching it as a zip file (hoping that that's reasonably easy to deal with these days) as well.  The outline-map-region line shows ^@ and ^K, whereas the actual backtrace includes null and control-K. 

Debugger entered--Lisp error: (wrong-type-argument integer-or-marker-p nil)$
 copy-marker(nil)$
 outline-map-region(#[nil "^H 	X\203\n^@\304 \207\n\210^K\207" [outline-level levels beg end outline-show-heading] 2] 47 nil)$
 hide-sublevels(1)$
 org-overview()$
 org-cycle-internal-global()$
 org-cycle((4))$
 org-set-startup-visibility()$
 org-mode()$
 set-auto-mode-0(org-mode nil)$
 set-auto-mode()$
 normal-mode(t)$
 after-find-file(nil t)$
 find-file-noselect-1(#<buffer foo.org> "~/tmp/foo.org" nil nil "~/tmp/foo.org" (12094261 234881026))$
 find-file-noselect("~/tmp/foo.org" nil nil t)$
 find-file("~/tmp/foo.org" t)$
 call-interactively(find-file nil nil)$

Please let me know if there's something else I can do to help.
*Chad