On Fri, Jul 3, 2009 at 22:43, RW<
rwmaillists@...> wrote:
>
> I think it might be worth having 2 XBL tests, a high scoring test on
> last-external and a lower-scoring test that goes back through the
> untrusted headers.
>
> I understand that Spamhaus doesn't recommend this, because dynamic IP
> addresses can be reassigned from a spambot to another user, but I added
> my own rule it does seem to work. In my mail it hits about 9% of my
> spam, with zero false-positives. I suspect that part of this is down to
> UK dynamic addresses being very sticky, but I ran my mailing lists
> through SA for a few weeks and got 3 FPs out of ~2400.
>
> I think it's probably worth a point or so, and essentially it's free
> - all of the zen lookups get done for SBL.
we used to do it this way, but the FPs are (surprisingly) high due to
dynamic-address-pool churn.
compare:
OVERALL% SPAM% HAM% S/O RANK SCORE NAME
5.100 10.1740 0.0200 0.998 0.65 0.01 T_RCVD_IN_XBL (with
trusted-networks)
5.417 10.6074 0.2203 0.980 0.18 0.00 RCVD_IN_XBL (with all nets)
I'll forward on the old mail for hysterical raisins.
--j.
