mail From control?

[stan]

I'm trying to set up a 4.11 STABLE machine to act as a mail host
for sevral virtual domains. 

I've got i moslty working, but I'm still strugling with SPF. I
_think_ the problem is that the messages coming from a user in
a virtual domain still contain a From header with the real name
of the machine. For example, using mutt I sent a message abck
to myself on this box, It contains the following:

From: stan <stan at i-v-o.net> 
which is the virtual domain, and ahs an SPF record.

But it _also_ has this header:

>From stan at ops2.ivo.net Sun Sep 18 11:03:14 2005

Which is the machine _real_ name. There is presently no SPF
record for this doamin.

sid-milter has this to say about this message:

Authentication-Results: ops2.ivo.net from=stan at i-v-o.net; sender-id=softfail; spf=neutral

I tried turing on the masqurade envolope feature in sendmail, but it did
not seem to change anything.

How can I force the outgoing mesage to appear to be from the virtual doamin
in all espects?

-- 
U.S. Encouraged by Vietnam Vote - Officials Cite 83% Turnout Despite Vietcong Terror 
- New York Times 9/3/1967