[EXIM] Spam filtering by Received: Lines

Hi.

After looking through the list archives and studiing some filter
examples, im not so sure if it can be done what I like to do.

I'd like to implement, in addition to the RBL and some direct sender
rejects by a local maintained list, a reject list for Received:
headers.

A small example of a mail:

Received: from mail.domainc.xx [1.2.3.4] 
    [...]
Received: from mail.domainb.xx [10.2.3.4] 
    [...]
Received: from mail.domaina.xx [100.2.3.4] 
    [...]

Now I've the problem, that some Spam mails get through because of open
hosts but one of the Received lines has one of well known spamer host
names or ranges (ala *.dialup.domainb.xx). As there is one or more
hosts inbetween, blocking on IP addresses is not possible.

Now I'd like to maintain two lists, one for hosts (host ranges) and
one for IPs and/or ranges.

Any Ideas how to implement this? Up till know, I don't see an easy
solution.

       Cheers,
       Oliver

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