[O] [BUG] Failure to run sh source block

[Christian Moe]

I've hit a couple of odd problems after updating to Emacs 24.5 and Org
8.3.4 (freshly pulled). 

Trying to run a simple shell source block, e.g.

#+begin_src sh
  pwd
#+end_src

fails with this error:

org-babel-variable-assignments:sh: Symbol's function definition is void:
org-babel-get-header


Yours,
Christian