[EXIM] Directors/routers and headers...

I've just come across another item for the wish list, if it's
possible. I'm currently running a couple of mailing lists through Exim
using the forwardfile director:

lists:
driver = forwardfile,
prefix = list-,
require_files = /etc/lists/${local_part},
senders = lsearch;/etc/lists/${local_part};
file = /etc/lists/${local_part},
no_check_local_user,
forbid_pipe,
forbid_file,
errors_to = request-${local_part}@???,
skip_syntax_errors,
syntax_errors_to = request-${local_part}@???,

I'd like to be able to add the appropriate headers to outgoing
messages that pass through this director for filtering purposes,
etc. as the Exim list does. Would it be possible to enable the
add_headers (and remove_headers, I suppose) generic option for
transports to also work for directors and routers, so I could use,
say:

  add_headers = "X-Loop: list-${local_part}@???\n\
                 X-Mailing-List: <list-${local-part}@???>"

?

Alistair

-- 
Computational Thaumaturge  --  Sysimperator, dominus retis deusque machinarum.
e-mail: avatar-sig@???      WWW: http://www.arkane.demon.co.uk/
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