[Exim] Junk Mail

Hi,

Does anyone know how to append a subject line if I receive spam. I tried
the following but the message passed through unchanged.

if $header_subject: contains "junk"
headers add "[JUNK]"
endif

Michael.

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                       Michael Daly
                    Research Engineer
            CAA Institute of Satellite Navigation
                    Leeds University
                      Leeds LS2 9JT

               E-mail: m.daly@???
                  Tel: +44 (0)113 343 2025
                  Fax: +44 (0)113 343 2032
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