Emails bouncing

[Roger]

Emails that I have been sending (from my BT Openworld account) to customers with accounts on cPanel have been bouncing with the error message local delivery failed I sent a full transcript to support yeaterday, but no acknowledgement yet. Here's a partial transcript of what I get back:
A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

jean@xxxxxxxxxxx.co.uk
local delivery failed

The following text was generated during the delivery attempt:

------ jean@xxxxxxxxxxx.co.uk ------

An error was detected while processing a file of BSMTP input.
The error message was:

421 Lost incoming connection

The SMTP transaction started in line 0.
The error was detected in line 3.
0 previous messages were successfully processed.
The rest of the batch was abandoned.
421 Lost incoming connection
Transaction started in line 0
Error detected in line 3

------ This is a copy of the message, including all the headers. ------
I wondered if anybody else has been getting this.
Roger

[othelloRob]

We had a few reports of this over a period of 3 days, almost exclusively from users of 2 ADSL providers.

I can reproduce the error when sending mail from a server with invalid reverse DNS - whilst looking up to see if its from a real mailserver or spammer, some ISPs mailservers are timing out (too short a negotiation/handshake).

We have implemented a few changes in place on the server to speed the checks at our end, and emailed the postmasters of ISPs suffering from the error.

This has fixed it for one customer, and those on BT/Yahoo stopped having the problems on Friday as far as we can tell.

Additionally, it's worth checking where you redirect your catch-all/main email account to - at least one of the reports of BSMTP failiures was a user-error in the control panel setting the redirection to a non-existant mailbox name.

Please let support know if you're still experiencing the problem