diff --git a/doc/src/sgml/ecpg.sgml b/doc/src/sgml/ecpg.sgml
index f9536ee1e4..1b34a6f75f 100644
--- a/doc/src/sgml/ecpg.sgml
+++ b/doc/src/sgml/ecpg.sgml
@@ -476,7 +476,7 @@ EXEC SQL COMMIT;
    In the default mode, statements are committed only when
    <command>EXEC SQL COMMIT</command> is issued. The embedded SQL
    interface also supports autocommit of transactions (similar to
-   <application>libpq</> behavior) via the <option>-t</option>
+   <application>psql</>'s default behavior) via the <option>-t</option>
    command-line option to <command>ecpg</command> (see <xref
    linkend="app-ecpg">) or via the <literal>EXEC SQL SET AUTOCOMMIT TO
    ON</literal> statement. In autocommit mode, each command is
diff --git a/src/backend/utils/misc/check_guc b/src/backend/utils/misc/check_guc
index 293fb0363f..d228bbed68 100755
--- a/src/backend/utils/misc/check_guc
+++ b/src/backend/utils/misc/check_guc
@@ -16,7 +16,7 @@
 ## if an option is valid but shows up in only one file (guc.c but not
 ## postgresql.conf.sample), it should be listed here so that it
 ## can be ignored
-INTENTIONALLY_NOT_INCLUDED="autocommit debug_deadlocks \
+INTENTIONALLY_NOT_INCLUDED="debug_deadlocks \
 is_superuser lc_collate lc_ctype lc_messages lc_monetary lc_numeric lc_time \
 pre_auth_delay role seed server_encoding server_version server_version_int \
 session_authorization trace_lock_oidmin trace_lock_table trace_locks trace_lwlocks \
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index d7142d218d..aca42436d3 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -171,7 +171,6 @@ static void assign_syslog_facility(int newval, void *extra);
 static void assign_syslog_ident(const char *newval, void *extra);
 static void assign_session_replication_role(int newval, void *extra);
 static bool check_temp_buffers(int *newval, void **extra, GucSource source);
-static bool check_phony_autocommit(bool *newval, void **extra, GucSource source);
 static bool check_bonjour(bool *newval, void **extra, GucSource source);
 static bool check_ssl(bool *newval, void **extra, GucSource source);
 static bool check_stage_log_stats(bool *newval, void **extra, GucSource source);
@@ -488,7 +487,6 @@ int			huge_pages;
  * and is kept in sync by assign_hooks.
  */
 static char *syslog_ident_str;
-static bool phony_autocommit;
 static bool session_auth_is_superuser;
 static double phony_random_seed;
 static char *client_encoding_string;
@@ -1250,17 +1248,6 @@ static struct config_bool ConfigureNamesBool[] =
 		false,
 		NULL, NULL, NULL
 	},
-	{
-		/* only here for backwards compatibility */
-		{"autocommit", PGC_USERSET, CLIENT_CONN_STATEMENT,
-			gettext_noop("This parameter doesn't do anything."),
-			gettext_noop("It's just here so that we won't choke on SET AUTOCOMMIT TO ON from 7.3-vintage clients."),
-			GUC_NO_SHOW_ALL | GUC_NOT_IN_SAMPLE
-		},
-		&phony_autocommit,
-		true,
-		check_phony_autocommit, NULL, NULL
-	},
 	{
 		{"default_transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT,
 			gettext_noop("Sets the default read-only status of new transactions."),
@@ -9179,18 +9166,6 @@ check_temp_buffers(int *newval, void **extra, GucSource source)
 	return true;
 }
 
-static bool
-check_phony_autocommit(bool *newval, void **extra, GucSource source)
-{
-	if (!*newval)
-	{
-		GUC_check_errcode(ERRCODE_FEATURE_NOT_SUPPORTED);
-		GUC_check_errmsg("SET AUTOCOMMIT TO OFF is no longer supported");
-		return false;
-	}
-	return true;
-}
-
 static bool
 check_bonjour(bool *newval, void **extra, GucSource source)
 {