[O] [BUG] `org-fill-paragraph' doesn't use `fill-prefix'

[Daniel Hackney]

I proposed a fix [1] for this back in 2010, but it seems to have regressed
again. `org-fill-paragraph' no longer makes use of a `fill-prefix', so
filling things like email comments no longer works.

To test, launch =emacs -Q= and create a buffer with

#+BEGIN_EXAMPLE
> The
> cat
> in
> the
> hat
#+END_EXAMPLE

And press =M-q=. In `fundamental-mode', this results in

#+BEGIN_EXAMPLE
> The cat in the hat
#+END_EXAMPLE

In recent versions of org-mode, this results in

#+BEGIN_EXAMPLE
> The > cat > in > the > hat
#+END_EXAMPLE

I have tested the following versions of org-mode:

  | Mode                             | Working |
  |----------------------------------+---------|
  | fundamental-mode                 | Yes     |
  | org 7.9.3f (Emacs 24.3.1)        | No      |
  | org 8.0 (20130727.224 from MELPA | No      |
  | 7.8.11 (Emacs 24.2.1)            | Yes     |
  |----------------------------------+---------|

P.S. I'm not subscribed to the list, so please CC me in replies.

[1] http://permalink.gmane.org/gmane.emacs.orgmode/22705

--
Daniel Hackney