[Exim] Autoreply (or similar) and return path.

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Ok, i know that autoreply uses a <> sender, and i know why.. But i would need to mimic the autoreply feature, but with a real return path

Right now i have the below. What i want to do is send a message to a adress, and have the message rewritten so that it has a set sender adress, and uses the incoming subject as the body of the outgoing text. Am i being unclear enough yet?

sms_handler:
        driver=accept
        local_parts = mobil
        domains = mupp.net
        transport = sms_gateway_transport

sms_gateway_transport:
driver = autoreply
user = mail
to = an-adress@???
from = nagios@???
text = $header_Subject:
return_message = false
log = /tmp/$local_part.log
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