[Orgmode] Bug: auto-fill in a body often inserts "#"

[Samuel Wales]

I am running the latest org-mode from the tar on emacs 22, installed
via macports, on a mac OS X Tiger default terminal.  I have turned on
auto-fill and set fill-column.

On the same setup with the default org-mode in emacs 22, this bug does
*not* happen.
Therefore, I think that it is either in the new code, or triggered by
the new code.

If I am at the end of a headline and press RET, then type alphabetic
characters and SPC as body text until auto-fill wraps, quite often the
second line will begin with a #.  There are no comment lines anywhere
nearby for auto-fill to adapt to.  This only happens in org-mode and
not in any other mode.

It sometimes happens and sometimes does not happen, which is strange.
I haven't tried it enough with emacs -q to be sure that it is or is
not something in my .emacs that is triggering the bug.  However, I
have no idea what could do this.

Any ideas?

Thanks.