[exim] treating moral config errors as serious

I've just had an embarrassing incident where a system upgrade
overwrote a customized greylistd, with the result that mail from new
senders was always deferred because of an invalid condition value, and
I didn't notice for more than a week.

On the whole, I feel that if during processing an ACL condition gets
an invalid value, that indicates a configuration error, and I'd like
exim to panic, since I will notice a panic quite quickly :)
Similarly for other run-time config file errors.

I don't see any option to make this kind of error get treated more
seriously - is there one that I've missed, or some other approach?