[EXIM] Can't get shadow_transport to work

I'm having problems getting a shadow transport to work. What I'm
trying to do is create an SMTP transaction log of all local
deliveries to provide a safety net during our upcoming sendmail->exim
conversion. With this log, if things don't go well I can just "play back"
the log into sendmail, and the old mbox spool will be synchronized with
the new maildir spool. This is using Exim 1.92 on HP-UX 11.0.

Configuration file:

# TRANSPORTS

shadow_local:
        driver = appendfile
        file = /var/log/bsmtp.log
        bsmtp = all
        prefix =
        suffix =
        user = exim

local_delivery:
        driver = appendfile
        maildir_format
        directory = ${local_part}
        group = mail
        mode = 0600
        shadow_transport = shadow_local

# END TRANSPORTS

The problem is that when I try to send a message that the local_delivery
transport will take care of, I get this in the logs:

1998-06-27 13:54:40 0ypzBP-0003PY-00 => james <james@???>
D=localuser T=local_delivery ST=shadow_local (Expansion of
"/tmp/smtp.batch/${host}" (file or directory name for shadow_local
transport) failed: )
1998-06-27 13:54:40 0ypzBP-0003PY-00 Completed

I've tried simplifying things, down to the point of using

file = /tmp/te

for shadow_local, but I get the same error message. Interesting, since
that string doesn't have any tokens to expand.

Any help appreciated.

--
j.

James FitzGibbon                                                james@???
System Engineer, ACC Global Net                   Voice/Fax (416)207-7171/7610

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