local mailboxes in thunderbird

looking on the net trying to solve a cooperation problem between
thunderbird and other mail programs, but not really finding the solution I
was looking for.  the closest guess I could find was this one:

On Tue, 28 Sep 2004 16:06:25 +0200, Volkmar W. Pogatzki wrote:
> Bryce Hardy wrote:
>> Are there any plans (or is there any way) to let TB retrieve mail from a
>> local mailbox directory (in my case, /var/mail/cygnia). I'm running SuSE
>> 9.1 and YAST2 automatically sets up my local mail system. I can use any of
>> the terminal programs like Pine and Mutt, or KMail, and even Evolution, but
>> TB doesn't offer any such functionality.
>> 
>> --
>> Bryce
> 
> Set up a new account and select "movemail"[1].
> It works perfectly, even with "multiple identities"[2]

I don't know if this solved the problem Bryce had, it does not solve my
interpretation of the problem...  first of all, to have it work at all, I
must chmod o+w /var/mail, which can't be a good thing.  

I also use Mutt and Balsa and both use the same ~/Mail directory, together
with /var/mail/mario. they cooperate nicely and I can read the same mail
from one client or the other without need for multiple copies of anything.

movemail removes or copies the content of /var/mail/mario into some
mozilla directory.  this is not the same and it is not desirable to me. 
I get at best two copies of each message...  no, it's not a solution.

any other hints?

thanks,
Mario

-- 
... hinc sequitur, unamquamque rem naturalem tantum iuris ex natura habere,
    quantum potentiae habet ad existendum et operandum ...
  -- Baruch de Spinoza, TRACTATUS POLITICUS