[Sheldon Hearn]
> I need to modify the Subject header for certain local recipients only.
In the local delivery transport(s), maybe you can do something along
the lines of:
headers_remove = subject
headers_add = Subject: ${if and {{<spam-filtering allowed for recipient>}\
{<spam-score is above threshold>}\
{<$h_subject: doesn't contain '[SPAM]'}}\
# Original value prefixed with '[SPAM] '
{[SPAM] $h_subject:}\
# Retain original value.
{$h_subject:}}
Note that this depends on the original Subject: still being available
to headers_add, even if the original header was selected for removal
by headers_remove. I have not tested that this is actually the case.
--
Harald