On Thu, 16 Jul 2009, Stefan Monnier wrote:

>>> Now would be a good time to submit it,
>> Ok. Is there any particular branch/repo/etc you'd like a patch against?
>
> CVS trunk.  Note that I haven't looked at your code yet.  Please send it
> to emacs-devel@gnu.org.

Here it is. The user can select the "word size" hexl will use with defcustom
(it currently screws up if you change this size behind hexl's back, ie 
after hexlifying a buffer but before unhexlifying it: this could be fixed 
by saving the word size used in a a local variable in the hexl buffer,
let me know if you think this is important enough to add). Other than that, 
the hexl code doesn't seem to have changed since I last updated the patch
from emacs 22 to emacs 23.

The word-size could also be chosen at invocation time via a prefix arg, but 
I have not done this yet either: Again, let me know if you think it's
worth adding.

I originally prepared this patch for a friend who was debugging something 
and needed other word sizes: Upon investigation I discovered that the
hexl binary had support for the word sizes 8, 16, 32 and 64 bits but the
hexl mode code only supported one of those - hence this patch.