Not in my experience. I'm using greylistd with Exim and a custom config which uses geolocation to do greylisting by subnet country code. I've only needed to whi

Not in my experience. I'm using greylistd with Exim and a custom config which uses geolocation to do greylisting by subnet country code. I've only needed to whitelist a handful of broken MTAs which don't retry. My spammers clearly haven't caught on yet... zgrep grey /var/log/exim4/rejectlog* | rev | cut -c 2-3 | rev | sort | uniq -c | sort -rn | head 8 CA 7 IT 5 ES 4 BR 4 AR 2 TR 2 RO 2 IR 2 EC 1 PT