On Aug 27, 2011, at 9:53 AM, Keith Moore wrote:
On Aug 26, 2011, at 8:18 PM, Hector Santos wrote:
Among the spammers rejected with delays, many do try a new transaction with
the same failed result. Is this CS client behavior? I seems to appear that
Maybe the spammers are trying to deal with greylisting?
For that matter, I wonder if legitimate senders are trying to deal with
greylisting also. Maybe there are poor implementations of greylisting that
block legitimate traffic too often. Maybe there are some large-volume senders
that don't want to deal with having greylisted mail in their queues any longer
than necessary. If retrying after a few seconds works on some greylists, it's
not surprising that some senders would start doing it.