30 hops max

router/620_local_dspam

dspam_router:
        no_verify
        #check_local_user
        # When to scan a message :
        # - it isn't already flagged as spam from Spamassassin
        # - it isn't already flagged as spam from DSPAM
        # - it isn't already scanned
        # - it isn't local
        # - it isn't from one internal domain user to another
        # - it is less than 512k in size
        require_files = /usr/local/bin/dspam
        condition   = "${if and { \
                {!def:h_X-FILTER-DSPAM:} \
                {!eq {$received_protocol}{local}} \
                { <= {$message_size}{512k}} \
                }\
                {1}{0}}"
        headers_add  = "X-FILTER-DSPAM: by $primary_hostname on $tod_full"
        driver       = accept
        transport    = dspam_spamcheck
        # Which users to run dspam for.
        local_parts = /etc/exim4/dspam_users

dspam_addspam_router:
        driver            = accept
        local_part_prefix = spam-
        transport         = dspam_addspam
        require_files = /usr/local/bin/dspam
        local_parts = /etc/exim4/dspam_users

dspam_falsepositive_router:
        driver            = accept
        local_part_prefix = nospam-
        transport         = dspam_falsepositive
        require_files = /usr/local/bin/dspam
        local_parts = /etc/exim4/dspam_users