Editing Simple Mail Transfer Protocol (section)

====8BITMIME====
At least the following servers advertise the 8BITMIME extension:
* [[Apache James]] (since 2.3.0a1)<ref>[http://james.apache.org/server/2.3.0/changelog.html James Server - ChangeLog] {{Webarchive|url=https://web.archive.org/web/20200220075532/http://james.apache.org/server/2.3.0/changelog.html |date=February 20, 2020 }}. James.apache.org. Retrieved on 2013-07-17.</ref>
* [[Citadel/UX|Citadel]] (since 7.30)
* [[Courier Mail Server]]
* [[Gmail]]<ref>8BITMIME service advertised in response to EHLO on gmail-smtp-in.l.google.com port 25, checked 23 November 2011</ref>
* [[IceWarp]]
* [[Internet Information Services|IIS]] SMTP Service
* [[Kerio Connect]]
* [[Lotus Domino]]
* [[Microsoft Exchange Server]] (as of Exchange Server 2000)
* [[Novell GroupWise]]
* [[OpenSMTPD]]
* [[Oracle Communications Messaging Server]]
* [[Postfix (software)|Postfix]]
* [[Sendmail]] (since 6.57)

The following servers can be configured to advertise 8BITMIME, but do not perform conversion of 8-bit data to 7-bit when connecting to non-8BITMIME relays:
* [[Exim]] and [[qmail]] do not translate eight-bit messages to seven-bit when making an attempt to relay 8-bit data to non-8BITMIME peers, as is required by the RFC.<ref>[https://archive.today/20120630212728/http://home.pages.de/~mandree/qmail-bugs.html Qmail bugs and wishlist]. Home.pages.de. Retrieved on 2013-07-17.</ref> This does not cause problems in practice, since virtually all modern mail relays are [[8-bit clean]].<ref>[http://cr.yp.to/smtp/8bitmime.html The 8BITMIME extension] {{Webarchive|url=https://web.archive.org/web/20110607045931/http://cr.yp.to/smtp/8bitmime.html |date=June 7, 2011 }}. Cr.yp.to. Retrieved on 2013-07-17.</ref>
* [[Microsoft Exchange Server]] 2003 advertises 8BITMIME by default, but relaying to a non-8BITMIME peer results in a bounce. This is allowed by {{IETF RFC|6152}}.<ref>{{cite IETF |rfc=6152|section=3|sectionname=The 8bit-MIMEtransport Service Extension |title=SMTP Service Extension for 8-bit MIME Transport|date=March 2011}}</ref>