As readers will have noticed, there has been some ongoing discussion
recently about the pros and cons of setting accept_8bitmime and what the
knock-on effects will be.
Mr Earnshaw drew to our attention the fact that the machines responding
as post.demon.nl, our customer smarthosts, were advertising 8BITMIME.
This was a mistake on our part and we have corrected it.
We appreciate Mr. Earnshaw's pointing out our mistake. It was the
result of an oversight by one of our mail administrators when initially
configuring our outgoing mail servers.
With regards to the actual impact of the misconfiguration, it seems to
have been minimal. The vast majority of mail-clients do use
Content-Transfer-Encoding to protect the data which they send. The only
client which is believed to not do so is Outlook for Macintosh, in some
versions. Our Support department reports no calls concerning this, so
our belief is that the impact has been close to zero.
This problem affected only the Exim mail servers used by our customers
for outgoing email. And, as noted above, few mail clients will have
attempted to use this advertised facility. This rather direct
experience of the lessened impact might be of note to the gentleman from
University of Kent at Canterbury, who was asking if it would cause
problems; we choose not to advertise 8BITMIME, others may arrive at a
different conclusion.
We do not accept that the use of MMDF for customer-bound mail in
itself causes mail corruption, as standards compliant MTAs will not
send 8 bit characters to MMDF. We regret that our misconfiguration led
to a non-standards-compliant MTA installation -- this is not policy.
We'd like to again repeat our commitment to migrate to Exim for all
customer mail-systems, for a number of reasons. 8-bit cleanliness is
one of those reasons. But not being 8-bit clean is not a problem for
an MTA, provided that it doesn't claim to be 8-bit clean.
Tony, are you in the Amsterdam area? Fancy a beer? We can continue to
discuss this off-list, as MMDF issues are not really relevant to Exim,
save where people have, erm, *coughs* set accept_8bitmime.
--
Systems Administrator, Network Operations Centre, Demon Internet Nederland
NL Sales: +31 20 422 20 00 Thus Plc NL Support: 0800 33 6666 8
