[EXIM] Conditional header rewriting

I have a number of questions, but will send them in separate messages
to keep the threads reasonable.

I am rewriting From lines, so that, for example

cc047@???

will come out as

J.Goldberg@???

This is working just fine, and was very easy to configure, with

*@partial-lsearch;/usr/info/exim/tables/urwhosts        \
        ${lookup{${lc:$1}}dbm{/usr/info/exim/tables/users}\
        {$value}fail}@??? f

I also want to rewrite header recipient lines for the domain part as
follows:

*@partial-lsearch;/usr/info/exim/tables/urwhosts $1@??? tcb

But, I want to do that rewriting (of recipient headers) if and only if
the message is from the hosts listed in urwhosts.

It stricks me that it must be easy to have something early in my rewriting
rules that has the effect of

if(! partial-lsearch;urwhosts ) fail fq

-j

--
Jeffrey Goldberg                +44 (0)1234 750 111 x 2826
 Cranfield Computer Centre      FAX         751 814
 J.Goldberg@???     http://WWW.Cranfield.ac.uk/public/cc/cc047/
Relativism is the triumph of authority over truth, convention over justice.

--
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