ellanios82 writes: > It's a pretty common requirement, as at one time it was the second > best spam defence (after accepting mail only for named users). Not so > good now that many ISPs are providing some kind of PTR record.
Some ISPs try to provide a single record for a group of their dynamic IPs. They bungle so that lookups fail for some IPs. And then some email providers apply that test to their own customers, *even after they have authenticated*. Hilarity ensues. Then there is "probing" the domain in the "From:" line... -- John Hasler j...@sugarbit.com Elmwood, WI USA
