diff -u postfix-2.11.0/debian/changelog postfix-2.11.0/debian/changelog
--- postfix-2.11.0/debian/changelog
+++ postfix-2.11.0/debian/changelog
@@ -1,3 +1,11 @@
+postfix (2.11.0-1ubuntu1.2) trusty; urgency=medium
+
+  * makedefs, src/util/sys_defs.h: Fix FTBFS with prior upload.
+    - Source assumes only Linux 3.x kernels exist, but HWE in trusty is
+      at 4.4.
+
+ -- Nishanth Aravamudan <nish.aravamudan@canonical.com>  Fri, 18 Aug 2017 18:13:13 -0700
+
 postfix (2.11.0-1ubuntu1.1) trusty; urgency=medium
 
   * Ignore broken symbolic links during ca_cert check (Closes LP: #1305232)
diff -u postfix-2.11.0/makedefs postfix-2.11.0/makedefs
--- postfix-2.11.0/makedefs
+++ postfix-2.11.0/makedefs
@@ -109,6 +109,8 @@
  # Officially supported usage.
  0) SYSTEM=`(uname -s) 2>/dev/null`
     RELEASE=`(uname -r) 2>/dev/null`
+    # No ${x%%y} support in Solaris 11 /bin/sh
+    RELEASE_MAJOR=`expr "$RELEASE" : '\([0-9]*\)'` || exit 1
     VERSION=`(uname -v) 2>/dev/null`
     case "$VERSION" in
      dcosx*) SYSTEM=$VERSION;;
@@ -369,7 +371,7 @@
 		       fi;;
 		esac
 		;;
-    Linux.3*)	SYSTYPE=LINUX3
+    Linux.[34].*)	SYSTYPE=LINUX$RELEASE_MAJOR
 		case "$CCARGS" in
 		 *-DNO_DB*) ;;
 		 *-DHAS_DB*) ;;
diff -u postfix-2.11.0/src/util/sys_defs.h postfix-2.11.0/src/util/sys_defs.h
--- postfix-2.11.0/src/util/sys_defs.h
+++ postfix-2.11.0/src/util/sys_defs.h
@@ -755,7 +755,7 @@
  /*
   * LINUX.
   */
-#if defined(LINUX2) || defined(LINUX3)
+#if defined(LINUX2) || defined(LINUX3) || defined(LINUX4)
 #define SUPPORTED
 #include <sys/types.h>
 #define UINT32_TYPE	unsigned int