[Exim] md5: operator?

This post in the mailing list archives uses the "md5" operator.

http://www.exim.org/mailman/htdig/exim-users/Week-of-Mon-20010416/025770.html

I've tried adding an md5 hash of the authenticated_id to my
received headers, but I keep getting (... added by me)

Expansion of "...
${if def:authenticated_id {(auth=${md5:${authenticated_id}}) }}
..." (received_header_text) failed: unknown expansion operator "md5"

I've searched the documentation and the mailing list for info,
but I can't seem to figure out how to get the md5 operator to work.

I have compiled my Exim binary with both authentication options
turned on.

What must I do to get the md5 operator to work?

Thanks,
Padraic


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Padraic Renaghan /pad-rik ren-a-han/
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