[Exim] defering a message

Hi all, we have a cron job that restarts spamassassin every hour, at
this time some spam slips through unfiltered. So I wanted to put in a
line to defer if the there was no spamassassin score header. I put the
following at the end of the data acl

defer condition=${if def:header_X-Spam-Score: {yes}{no}}

It seemed to work in tests but I am still seeing some spam get through
unfiltered, in that it has no X-Spam-score header, though it definitely
came through the spam filtering server. Any suggestions on an improved
way to do this much appreciated.

Evey email that comes through that server should have a spam score, I
don't understand why occasionally one comes through wiht no spam score.

Ron

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Ron McKeating
Senior IT Services Specialist
Internet Services and Software Solutions
Loughborough University
01509 222329