Getting the right From: line

Hi all,

I have been trying to have a proper From: line when I send mail
from my laptop, but things are not going right. The problem is, in
the laptop I am user "joao", and when I connect at the university
and send mail, the From: line leaves as

   From: [email protected]

and I want it to leave as

   From: [email protected]

because that is my username at the university. Up to now I have
been inserting a Reply-To: field in the components file, but now
I want to do things right, and masquerade the username in the From:.

So, I tried to edit mts.conf and set masquerading, but both
draft_from and mmailid options are producing strange From lines that
still contain the "joao" address. Some of those lines look like this:

with mmailid:
From: "\"\" Joao B.Oliveira \" \"" <"[email protected]"@inf.pucrs.br>

with draft_from:
From: [email protected] ("Joao B. Oliveira" <[email protected]>)

This is obvioulsy not what I want... Does anyone have hints? I am
using Linux Ubuntu 5.10, with exmh 2.7.2 and nmh 1.1.3.

thanks,

joao