--- "Kurt A. Schumacher" <Kurt.Schumacher(a)schumi.ch> wrote:
> Just a guess:
> The more retries to a certain SMTP destination, the longer the retry
> interval...leads to exponential delivery times.
no, it's quite sporadic: some emails are retried wihtin 10 minutes,
and some were delaying for hours.
> Pure greylisting is - just like blacklistsing - is useless or leads to
> unexpected behavior without a well-maintained and monitored whitelist for a
> corporate or ISP e-mail system.
it is actually a well-maintained whitelist, but of course sometimes
exceptions happen...