diff --git a/config.h.in b/config.h.in
index 69adebae..b977437d 100644
--- a/config.h.in
+++ b/config.h.in
@@ -2,4 +2,3 @@
 
 /* Only build repmgr for BDR */
 #undef BDR_ONLY
-
diff --git a/configure b/configure
index 71c256d4..08d3eca4 100755
--- a/configure
+++ b/configure
@@ -1841,7 +1841,7 @@ if test "$major_version_num" -lt '10'; then
     version_num_int=$(echo "$version_num"|
                     $SED -e 's/^\([0-9]*\)\.\([0-9]*\)$/\1\2/')
 
-    if test "$version_num_int" -lt '94'; then
+    if test "$version_num_int" -lt '93'; then
         as_fn_error $? "repmgr is not compatible with detected PostgreSQL version: $version_num" "$LINENO" 5
     fi
 else
diff --git a/configure.in b/configure.in
index 7f036c11..3fd4f30a 100644
--- a/configure.in
+++ b/configure.in
@@ -38,7 +38,7 @@ if test "$major_version_num" -lt '10'; then
     version_num_int=$(echo "$version_num"|
                     $SED -e 's/^\([[0-9]]*\)\.\([[0-9]]*\)$/\1\2/')
 
-    if test "$version_num_int" -lt '94'; then
+    if test "$version_num_int" -lt '93'; then
         AC_MSG_ERROR([repmgr is not compatible with detected PostgreSQL version: $version_num])
     fi
 else
diff --git a/repmgr--4.0.sql b/repmgr--4.0.sql
index 8621d921..b84c87f3 100644
--- a/repmgr--4.0.sql
+++ b/repmgr--4.0.sql
@@ -23,6 +23,16 @@ CREATE TABLE repmgr.events (
   details          TEXT NULL
 );
 
+DO $repmgr$
+DECLARE
+  DECLARE server_version_num INT;
+BEGIN
+  SELECT setting
+    FROM pg_catalog.pg_settings
+   WHERE name = 'server_version_num'
+    INTO server_version_num;
+  IF server_version_num >= 90400 THEN
+    EXECUTE $repmgr_func$
 CREATE TABLE repmgr.monitoring_history (
   primary_node_id                INTEGER NOT NULL,
   standby_node_id                INTEGER NOT NULL,
@@ -32,7 +42,26 @@ CREATE TABLE repmgr.monitoring_history (
   last_wal_standby_location      PG_LSN,
   replication_lag                BIGINT NOT NULL,
   apply_lag                      BIGINT NOT NULL
-);
+)
+    $repmgr_func$;
+  ELSE
+    EXECUTE $repmgr_func$
+CREATE TABLE repmgr.monitoring_history (
+  primary_node_id                INTEGER NOT NULL,
+  standby_node_id                INTEGER NOT NULL,
+  last_monitor_time              TIMESTAMP WITH TIME ZONE NOT NULL,
+  last_apply_time                TIMESTAMP WITH TIME ZONE,
+  last_wal_primary_location      TEXT NOT NULL,
+  last_wal_standby_location      TEXT,
+  replication_lag                BIGINT NOT NULL,
+  apply_lag                      BIGINT NOT NULL
+)
+    $repmgr_func$;
+  END IF;
+END$repmgr$;
+
+
+
 CREATE INDEX idx_monitoring_history_time
           ON repmgr.monitoring_history (last_monitor_time, standby_node_id);
 
@@ -73,10 +102,33 @@ CREATE FUNCTION standby_get_last_updated()
 
 /* failover functions */
 
+
+DO $repmgr$
+DECLARE
+  DECLARE server_version_num INT;
+BEGIN
+  SELECT setting
+    FROM pg_catalog.pg_settings
+   WHERE name = 'server_version_num'
+    INTO server_version_num;
+
+  IF server_version_num >= 90400 THEN
+    EXECUTE $repmgr_func$
 CREATE FUNCTION request_vote(INT,INT)
   RETURNS pg_lsn
   AS 'MODULE_PATHNAME', 'request_vote'
   LANGUAGE C STRICT;
+    $repmgr_func$;
+  ELSE
+    EXECUTE $repmgr_func$
+CREATE FUNCTION request_vote(INT,INT)
+  RETURNS TEXT
+  AS 'MODULE_PATHNAME', 'request_vote'
+  LANGUAGE C STRICT;
+    $repmgr_func$;
+  END IF;
+END$repmgr$;
+
 
 CREATE FUNCTION get_voting_status()
   RETURNS INT
diff --git a/repmgr.c b/repmgr.c
index af54ecaf..de1deb3f 100644
--- a/repmgr.c
+++ b/repmgr.c
@@ -20,6 +20,7 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+
 #include "postgres.h"
 #include "fmgr.h"
 #include "access/xlog.h"
@@ -31,7 +32,13 @@
 #include "storage/shmem.h"
 #include "storage/spin.h"
 #include "utils/builtins.h"
+
+#if (PG_VERSION_NUM >= 90400)
 #include "utils/pg_lsn.h"
+#else
+#include "compat-lsn.h"
+#endif
+
 #include "utils/timestamp.h"
 
 #include "executor/spi.h"
diff --git a/repmgr.h b/repmgr.h
index 5b5ec855..ff8f4022 100644
--- a/repmgr.h
+++ b/repmgr.h
@@ -26,6 +26,8 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
+#include <sys/types.h>
 
 #include <libpq-fe.h>
 #include <postgres_fe.h>
@@ -39,8 +41,8 @@
 #include "dbutils.h"
 #include "log.h"
 
-#define MIN_SUPPORTED_VERSION		"9.4"
-#define MIN_SUPPORTED_VERSION_NUM	90400
+#define MIN_SUPPORTED_VERSION		"9.3"
+#define MIN_SUPPORTED_VERSION_NUM	90300
 
 #define REPLICATION_TYPE_PHYSICAL 1
 #define REPLICATION_TYPE_BDR	  2