> NO - it does not! Well, not unless the sending MTA is broken. To quote > from Postfix documentation referring to not getting an MX record from > DNS: > " By default, the Postfix SMTP client defers delivery and tries again > after some delay. This behavior is required by the SMTP standard."
Yes it does. I've run an ISP with about 3000 accounts and currently manage the spam filter and virus filter for the campus here with about 20,000 accounts, so I have had plenty of opportunity to see this happen. There are many broken clients and MTAs out there. G
