exim: how to modify the "Sender:" header

["Rahmat M. Samik-Ibrahim" <rms46@vlsm.org>]

Hello:

My debian system is inside an intranet, and therefore
I use a smart host for forwarding emails. There is a problem
on how to set the "Sender:" header of an email.
It seems that the smarthost adds "Sender:user@smarthost.FQDN"
since (apparently) neither exim nor netscape (mail reader)
put an appropriate FQDN.

I try to fix this problem by forcing the "exim.conf":

------------------------------------------------------------
smarthost:
  driver = domainlist
  transport = remote_smtp
  route_list = "* SMART_HOST.FQDN bydns_a"
  headers_remove = "Sender"
  headers_add = "Sender: <USER@OTHER.FQDN>"
end
-----------------------------------------------------------

where SMART_HOST.FQDN is the smarthost and USER@OTHER.FQDN
is my email address. Unfortunately, this way will make ALL 
emails (from any local users) to have:
          "Sender: <USER@OTHER.FQDN>"

Is there a better way to configure the exim.conf?

regards,

-- 
Rahmat M. Samik-Ibrahim - VLSM-TJT - http://rms46.vlsm.org
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