[nycbug-talk] greylisting proxies?

[Francisco Reyes]

George Georgalis writes:

> and greylisting purges 97% of of them, with low (0?) false positives.

Only problem, I know of, with Greylisting is that some (non spammer)  
companies use special delivery programs. In particular I have seen American 
Express uses such a system. They will take the initial error as permanent..

This however is the exeption and some greylisting implementations have a 
list of known companies that have this problem.

I am using sqlgrey and they have a list of IPs from companies that their 
systems will take the temporary failure as permanent and not retry. They 
also update the list and you can get the latest list from them.