[exim] Sender based copy router ...

Hi !

I have just been trying to write an exim router which checks
'$sender_address' and based upon its findings it should send a duplicate
message to an extra mailbox.

I have come to the following:

---

addresslist sender_forward_list = /etc/exim/sendby_senders

check_outgoing:
debug_print = "R: extra-forward based on $sender_address"
driver = redirect
allow_fail
allow_defer
senders = +sender_forward_list
data = ${lookup{$sender_address}lsearch{/etc/exim/sendby_forwardlist}}
repeat_use = false
unseen

---

but this requires 2 files.

1. "sendby_senders", a plain text file containing all the sender addresses
to be monitored
2. "sendby_fowardlist", a plain text file containing (againg) all senders,
and the address to forward a copy to.

I hope someone can help me with the following questions:

a) Is is possible to combine the 2 file into 1 with a syntax like
"sender@???: copyadress@???"
b) Can I change the subject into something like "[$sender_address ->
$local_part@$domain] $originalsubject".

bye,
Chris