[Exim] Exim Filter

Hello can someone help me with a mail filter..

I want exim to check e-mails if the subject line = something to not send
it to the original user but to send it to a file instead.

ie.
if $header_subject contains "Important Message From" then
cat /to/a/file/somehow
endif

Could someone tell me how I really save it to a file?


Regards
Scott Stavretis
CDI Network Manager
Connect Direct Internet
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