In the grand tradition of johnsmithsvt, we’ve started seeing spam for mmskuramoto. None of it has been allowed into the system, since it’s coming from a blacklisted IP, so I don’t know what flavor the spam is, but the attempts were surprisingly well-behaved: most spammers treat the 451 we return to blacklisted IPs the same as a 5xx error (they retry maybe once, maybe fifty times, right away, then give up); the mmskuramoto sender backed off the retries very nicely. So nicely, in fact, that I got the originating IP whitelisted and the alias added, just so I could see what the spam was. Unfortunately (or not, probably), they gave up after 14 tries, just a couple hours before they would have gotten through.
For those who care, the blacklisting setup has been modified somewhat since the johnsmithsvt post referred to above: all country-based blocking is done with zz.countries.nerd.dk, but most of the blocking ends up happening because of a bunch of Class A and B size blocks (virtually anything in apnic or south america). We still use zen.spamhaus.org, combined.njabl.org, bl.spamcop.net, dnsbl.sorbs.net, and dnsbl.jammconsulting.com, and they contribute (especially zen), but it’s mostly the huge swaths of net that are blacklisted.