RE:The block message is 521 DNSRBL: Blocked for abuse

Here's a thought. Would it be possible to set up a process where ARIN, as part of reselling IP addresses, either issues a certificate of transfer that the new owner can use to prove to the ISPs that he's a new owner and not the old evil spammer, or ARIN publishes a list of IP assignments that can be used by ISPs to provisionally remove them from blocked lists? I sympathize with the original poster, it's sort of like buying a used car, only to find out the previous owner was the drunk driver who ran over your next door neighbor's dog.