diff -Nru exim4-4.76/debian/changelog exim4-4.76/debian/changelog
--- exim4-4.76/debian/changelog	2012-10-25 16:26:54.000000000 +0400
+++ exim4-4.76/debian/changelog	2012-12-09 11:35:56.000000000 +0400
@@ -1,3 +1,11 @@
+exim4 (4.76-3ubuntu3.2) precise-proposed; urgency=low
+
+  * Increase smtp_cmd_buffer_size to 16384 (upstream bug #879, fixed in 4.77).
+    This allows using smtp kerberos/gssapi auth against AD/samba4 on windows.
+    (LP:#1088136)
+
+ -- Sergey Urushkin <urusha.v1.0@gmail.com>  Sun, 09 Dec 2012 11:24:05 +0400
+
 exim4 (4.76-3ubuntu3.1) precise-security; urgency=low
 
   * SECURITY UPDATE: arbitrary code execution via dns decode logic
diff -Nru exim4-4.76/debian/patches/71_increase_smtp_cmd_buffer_size.patch exim4-4.76/debian/patches/71_increase_smtp_cmd_buffer_size.patch
--- exim4-4.76/debian/patches/71_increase_smtp_cmd_buffer_size.patch	1970-01-01 03:00:00.000000000 +0300
+++ exim4-4.76/debian/patches/71_increase_smtp_cmd_buffer_size.patch	2012-12-09 11:34:57.000000000 +0400
@@ -0,0 +1,24 @@
+Description: Increase smtp_cmd_buffer_size to 16384
+Author:  Paul Fisher <pnfisher@berkeley.edu>
+Forwarded: http://bugs.exim.org/show_bug.cgi?id=879
+Bug-Ubuntu: https://bugs.launchpad.net/ubuntu/+source/exim4/+bug/1088136
+
+diff -u -r exim-4.69/src/smtp_in.c exim-4.69-cmd-buffer/src/smtp_in.c
+--- exim-4.69/src/smtp_in.c	2007-09-28 05:21:57.000000000 -0700
++++ exim-4.69-cmd-buffer/src/smtp_in.c	2009-08-13 20:09:12.000000000 -0700
+@@ -37,9 +37,14 @@
+ /* Size of buffer for reading SMTP commands. We used to use 512, as defined
+ by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP
+ commands that accept arguments, and this in particular applies to AUTH, where
+-the data can be quite long. */
++the data can be quite long.  More recently this value was 2048 in Exim; 
++however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH.  Clients
++such as Thunderbird will send an AUTH with an initial-response for GSSAPI. 
++The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and 
++we need room to handle large base64-encoded AUTHs for GSSAPI.
++*/
+ 
+-#define smtp_cmd_buffer_size  2048
++#define smtp_cmd_buffer_size  16384
+ 
+ /* Size of buffer for reading SMTP incoming packets */
diff -Nru exim4-4.76/debian/patches/series exim4-4.76/debian/patches/series
--- exim4-4.76/debian/patches/series	2012-10-25 16:26:22.000000000 +0400
+++ exim4-4.76/debian/patches/series	2012-12-09 11:13:04.000000000 +0400
@@ -10,3 +10,4 @@
 67_unnecessaryCopt.diff
 70_remove_exim-users_references.dpatch
 CVE-2012-5671.patch
+71_increase_smtp_cmd_buffer_size.patch