[Lost track of who wrote this] > 66.96.253.241 > 64.120.241.228 > 66.197.142.29 > 66.197.142.23 > 66.197.207.152 > 66.197.177.174 > 64.191.61.25
Every single one of those IPs is on our "GreylistStumbler" list, meaning they've been greylisted, but have not been seen to pass greylisting. Implementing greylisting might stop most of the problem messages. Regards, David.