[Exim] anti-relay

Hi,

i am looking for a method to prevent spamming from my exim. I've got not
static list of ips that are allowed to relay via my exim. The list is
dynamic. So i use host_accept_relay = +allow_unknown : 127.0.0.1 :
localhost : lsearch;/etc/relayhosts
The problem with this setting is that everbody who has no PTR on his
domain can relay thru my exim. I chose this setting, because people who
have no ptr but who's ips are enlisted in the /etc/relayhosts were not
allowed to relay.
My question is whether there's a possibility to just check the IP-Adress
of the client who wants to relay and not check whether he has an ptr or
not. This would let me take out the +allow_unknown.

Thanks

andreas gietl

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andreas gietl
gietl internet services
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fon +49 941 3810884
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