[exim] Debugging autoreply transport

Hi,

I've been experimenting with vacation msgs, using an accept
router, and an autoreply transport, which all seem pretty
standard. The message routes fine, and the conditions in the
accept router all seem to be satisfied, but when debugging
the whole lifetime of the message, I got errors when the
child delivery process for the autoreply transport is called.
This _only_ happens in debugging mode. The errors were similar
to the following:

826 cwd=/home/emma 8 args: /usr/exim/bin/exim -d=0xfbbd5cfd -t -oem -oi -f <>
-E1GDQC6-0000D5-GT
exim: debugging permission denied
825 vacation_reply transport succeeded
825 search_tidyup called
818 vacation_reply transport returned DEFER for emma@???
818 added retry item for T:emma@???: errno=0 more_errno=0 fla
gs=0
818 post-process emma@??? (1)
818 LOG: MAIN
818 == emma@??? R=user_vacation T=vacation_reply defer (0):
Failed to send message from vacation_reply transport (1)
818 >>>>>>>>>>>>>>>> deliveries are done >>>>>>>>>>>>>>>>

Does this mean that I cannot debug this transport at all if it
runs as an unprivileged user? Why does the transport think it
succeeded, and why is the vacation msg not put on the queue for
later delivery? As I said above, if I don't run in debugging
mode, I don't get this error, and blocking outgoing port 25
connections allows the auto response message to be enqueued
just fine.

Thanks for any feedback.

Cheers,

===Rich