diff --git a/man/mosquitto.conf.5.xml b/man/mosquitto.conf.5.xml
index e3e64c9d..16269671 100644
--- a/man/mosquitto.conf.5.xml
+++ b/man/mosquitto.conf.5.xml
@@ -351,13 +351,16 @@
 						contain the main configuration file.</para>
 					<para>The configuration files in
 						<option>include_dir</option> are loaded in case
-						insensitive alphabetical order.</para>
+						sensitive alphabetical order, with the upper case of
+						each letter ordered before the lower case of the same
+						letter.</para>
 						<example title="Load Order for include_dir" label="Load Order for include_dir">
 							<para>Given the files
 								<replaceable>b.conf</replaceable>,
 								<replaceable>A.conf</replaceable>,
 								<replaceable>01.conf</replaceable>,
-								<replaceable>a.conf</replaceable>, and
+								<replaceable>a.conf</replaceable>,
+								<replaceable>B.conf</replaceable>, and
 								<replaceable>00.conf</replaceable> inside
 								<option>include_dir</option>, the config files
 								would be loaded in this order:</para>
@@ -366,6 +369,7 @@
 01.conf
 A.conf
 a.conf
+B.conf
 b.conf
 </programlisting></example>
 					<para>If this option is used multiple times, then each
diff --git a/mosquitto.conf b/mosquitto.conf
index c974eaf3..9a1ba231 100644
--- a/mosquitto.conf
+++ b/mosquitto.conf
@@ -872,10 +872,10 @@
 # in the main file. This option will only be processed from the main
 # configuration file. The directory specified must not contain the 
 # main configuration file.
-# Files within include_dir will be loaded sorted in case-insensitive
-# alphabetical order. If this option is given multiple times, all of the files
-# from the first instance will be processed before the next instance. See the
-# man page for examples.
+# Files within include_dir will be loaded sorted in case-sensitive
+# alphabetical order, with capital letters ordered first. If this option is
+# given multiple times, all of the files from the first instance will be
+# processed before the next instance. See the man page for examples.
 #include_dir
 
 # =================================================================
diff --git a/src/conf_includedir.c b/src/conf_includedir.c
index 4d99f892..b0aecf2c 100644
--- a/src/conf_includedir.c
+++ b/src/conf_includedir.c
@@ -16,6 +16,7 @@ Contributors:
 
 #include "config.h"
 
+#include <ctype.h>
 #include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -47,12 +48,33 @@ Contributors:
 #include "mqtt3_protocol.h"
 
 
-#ifdef WIN32
 int scmp_p(const void *p1, const void *p2)
 {
-	return strcasecmp(*(const char **)p1, *(const char **)p2);
+	const char *s1 = *(const char **)p1;
+	const char *s2 = *(const char **)p2;
+	int result;
+
+	while(s1[0] && s2[0]){
+		/* Sort by case insensitive part first */
+		result = toupper(s1[0]) - toupper(s2[0]);
+		if(result == 0){
+			/* Case insensitive part matched, now distinguish between case */
+			result = s1[0] - s2[0];
+			if(result != 0){
+				return result;
+			}
+		}else{
+			/* Return case insensitive match fail */
+			return result;
+		}
+		s1++;
+		s2++;
+	}
+
+	return s1[0] - s2[0];
 }
 
+#ifdef WIN32
 int config__get_dir_files(const char *include_dir, char ***files, int *file_count)
 {
 	int len;
@@ -112,10 +134,6 @@ int config__get_dir_files(const char *include_dir, char ***files, int *file_coun
 
 
 #ifndef WIN32
-int scmp_p(const void *p1, const void *p2)
-{
-	return strcmp(*(const char **)p1, *(const char **)p2);
-}
 
 int config__get_dir_files(const char *include_dir, char ***files, int *file_count)
 {