News
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Low-level changes include a rework of the event-loops. The Unix event loop
defaults to an epoll() implementation.

The i18n of the main server (not the gui) has been extended somewhat by marking
for translation the text of most C++ exceptions. This is only relevant if
building "--with-gettext" and running with "--localedir".

The "--anonyous" option has changed slightly in v2.4 so that it will now force
the AUTH parameter on the MAIL command to be "AUTH=<>". Replace "--anonymous"
with "--anonymous=vrfy,server,content" to keep the same behaviour as before.

The "emailrelay-submit" utility's "--content" option no longer suppresses
reading of the standard input stream; there is a new "--no-stdin" option
instead. A dot on its own does not terminate the input any more, so use ^D or
^Z to stop reading from the terminal. Header-only content with no body text is
now permitted.

Authentication using PAM no longer insists on TLS encryption because the
"--server-auth-config" option can be used to disable password authentication
over an unencypted connection.

Limited support for routing is included. The envelope files have two new fields:
ForwardTo and ForwardToAddress. A filter script can examine the message content
and deposit the appropriate domain name and port number in the ForwardTo field.
If the SMTP client sees a ForwardTo value then it runs the client-filter early
allowing the client filter to do a DNS MX lookup of the ForwardTo value and
deposit the address into the ForwardToAddress field. If the SMTP client sees a
ForwardToAddress it will initiate a connection to that address to send the
message. The client-filter is run a second time in the normal way once the SMTP
session has been established. A connection to the main "--forward-to" address
will always be made even if all the messages are routed elsewhere, and each
routed connection will carry only one message.