compatibility of nnml and MH

[Jason R Mastaler <jason@mastaler.com>]

How compatibile is the nnml backend with MH and how uncompatible is it
with MH?  If I have a bunch of nnml groups and save articles from
those groups to existing MH folders with `O h', do I have to worry
that those saved articles are no longer MH compliant in some way
because their origin was an nnml group?  Or, does the origin not
matter in this case since I used `O h' to save?

  `O h'
     Save the current article in mh folder format

I'm not interested in reading existing nnml groups with MH or MH
front-end, but I am interested in being able to manipulate saved
articles from those nnml groups at a later date with MH and not run
into problems.  I hope I'm making sense here.

Also, there seems to be conflicting ideas about the compatibility
of nnml with other formats (such as MH).  

On one hand nnml is supposedly not at all compatible with other
formats..

The manual says of nnml:
 
  The "nnml" spool mail format isn't compatible with any other known
  format.  It should be used with some caution.

Lars wrote to ding:

  Uhm.  Nope.  nnml is nnml, while nnmh is supposed to be mh compliant.
  nnml will never be able to coexist with mh.  That the point of nnmh. 

On the other hand..

The manual says of nnmh:

  `nnmh' is just like `nnml', except that is doesn't generate NOV
  databases and it doesn't keep an active file.  This makes `nnmh' a
  *much* slower backend than `nnml', but it also makes it easier to
  write procmail scripts for.

This seems to imply that nnml is somewhat compatable with MH since
nnmh (which is MH compliant) is "just like `nnml', except that is
doesn't generate NOV databases and it doesn't keep an active file".
Is the existance of the NOV databases and active file enough to
introduce these incompatibilities?  It really doesn't seem like it
could, so is there something else I've missed?

   Jason R. Mastaler                      jason@mastaler.com