According to spec.txt, headers_rewrite is used at transport time to
rewrite headers. And it says:
"However, only the message's original header lines, and any
that were added by a system filter, are rewritten."
But it doesn't seem to rewrite headers added by a system filter.
I demonstrated this by adding
headers add "Reply-to: wmb@k2di"
to my system filter and passing the same header to exim as input.
The transport's headers_rewrite command converts such addresses to
"k2di2@???" -- but only the line passed as input was rewritten.
I'm using version 4.20.
--
Bill Brelsford
k2di2@???