<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=windows-1252">
</head>
<body text="#000000" bgcolor="#FFFFFF">
<font face="Arial">Hello,<br>
<br>
It is my understanding that the Debian developers plan to include
exim version 4.84 or 4.85 with the Debian 8 Jessie release. I
have several mail servers running exim4 on Debian 7 Wheezy and I
want you to be aware of a nasty little bug in exim versions 4.83,
4.84 and 4.85. I am bringing this to your attention in an effort
to ensure that this bug is patched in whatever version of exim4
that you include with Jessie. </font><br>
<font face="Arial"><font face="Arial"><font face="Arial"><font
face="Arial"><br>
Specifically, this bug prevents header manipulation which is
common for users running spam prevention software such as
Spamassassin where exim can optionally remove and/or add
headers such as Spamassassin's X-Spam-Report, X-Spam-Score,
and/or tag the Subject header as spam, etc. This regression
also impacts both the Exim4U and Vexim2 software
configurations for exim4. For more info on Exim4U and
Vexim2, see:<br>
<br>
<a class="moz-txt-link-freetext" href="http://exim4u.org/index.html">http://exim4u.org/index.html</a><br>
<a class="moz-txt-link-freetext" href="https://github.com/avleen/vexim2">https://github.com/avleen/vexim2</a><br>
<a class="moz-txt-link-freetext" href="http://stefans.datenbruch.de/rootserver/vexim.shtml">http://stefans.datenbruch.de/rootserver/vexim.shtml</a><br>
<br>
</font></font></font></font><font face="Arial">This regression
was initially introduced in exim 4.83 which caused the
headers_remove clauses in the exim configuration files to
malfunction. This regression continued in Exim 4.84 and 4.85. </font><font
face="Arial"><font face="Arial">Exim versions earlier than exim
4.83 are not impacted by this regression. </font> A partial
fix was implemented in 4.85 which fixed the transports section but
not the routers section. The bug report is here:<br>
<br>
<a class="moz-txt-link-freetext"
href="http://bugs.exim.org/show_bug.cgi?id=1533">http://bugs.exim.org/show_bug.cgi?id=1533</a><br>
</font><font face="Arial"><font face="Arial"><font face="Arial"><br>
</font></font>At the bottom of this bug report is a patch for
the routers section. </font><font face="Arial"><font
face="Arial">I patched exim 4.85 on a FreeBSD installation </font><font
face="Arial"><font face="Arial">as per bug 1533</font>. </font>Another
exim user, Shamim Shahriar, and I have tested this patch on
FreeBSD and it appears to fix the regression altogether. Please
also note that, in the exim runtime configuration file (for
Debian: exim4.conf), additional modifications must also be made
for installations that use mysql statements in the headers_remove
clauses. </font><font face="Arial"><font face="Arial"> That is,
the colon ":" in </font>any quote_mysql statements that are
included in the headers_remove clauses must be replaced with
double colons "::" for the patched version of Exim 4.85 to work
properly.</font><font face="Arial"><br>
<br>
Users running unpatched versions of exim </font><font
face="Arial"><font face="Arial">4.83, 4.84 & 4.85 must comment
out all of the headers_remove clauses which include quote_mysql
statements altogether for exim to work, otherwise it will
malfunction and not deliver mail properly. This will, of
course, remove features related to header removal so its not the
preferred solution</font></font><font face="Arial"><font
face="Arial"><font face="Arial">.<br>
<br>
So, again, please consider including this patch in the exim4
release for Debian 8 Jessie. Alternatively, I recommend that
you include an exim version earlier than 4.83.<br>
<br>
Thanks and I hope that you find this information useful,<br>
<br>
Gordon Dickens</font></font></font><br>
</body>
</html>