diff --git a/src/feature.c b/src/feature.c
index cbbd7a8..1129abe 100644
--- a/src/feature.c
+++ b/src/feature.c
@@ -137,7 +137,7 @@ check_string_in_guc_list(const char *str, const char *guc_var, const char *guc_n
 	ListCell   *lc;
 
 	guc_copy = pstrdup(guc_var);
-	if (!SplitIdentifierString(guc_copy, ',', &guc_list))
+	if (!SplitGUCList(guc_copy, ',', &guc_list))
 		elog(ERROR, "could not parse %s", guc_name);
 
 	foreach(lc, guc_list)
diff --git a/test/t/004_pg_tle_clientauth.pl b/test/t/004_pg_tle_clientauth.pl
index 1f2c434..332a7e7 100644
--- a/test/t/004_pg_tle_clientauth.pl
+++ b/test/t/004_pg_tle_clientauth.pl
@@ -166,8 +166,9 @@
     "clientauth function does not reject testuser2 when clientauth is enabled without restart");
 
 ### 9. Functions do not take effect when user is on pgtle.clientauth_users_to_skip
+$node->psql('postgres', 'CREATE ROLE testUser3 LOGIN', stderr => \$psql_err);
 $node->append_conf('postgresql.conf', qq(pgtle.enable_clientauth = 'on'));
-$node->append_conf('postgresql.conf', qq(pgtle.clientauth_users_to_skip = 'testuser,testuser2'));
+$node->append_conf('postgresql.conf', qq(pgtle.clientauth_users_to_skip = 'testuser,testuser2,testUser3'));
 $node->restart;
 
 $node->command_ok(
@@ -176,6 +177,9 @@
 $node->command_ok(
     ['psql', '-U', 'testuser2', '-c', 'select;'],
     "clientauth function does not reject testuser2 when testuser2 is in pgtle.clientauth_users_to_skip");
+$node->command_ok(
+    ['psql', '-U', 'testUser3', '-c', 'select;'],
+    "clientauth function does not reject testUser3 when testUser3 is in pgtle.clientauth_users_to_skip");
 
 ### 10. Functions do not take effect when database is on pgtle.clientauth_databases_to_skip
 $node->psql('postgres', 'CREATE DATABASE not_excluded');
@@ -254,6 +258,47 @@
             END IF;
         END
     $$ LANGUAGE plpgsql], on_error_die => 1);
+### 16. Allow mixedCase in pgtle.clientauth_users_to_skip
+$node->psql('postgres', 'CREATE ROLE testUser3 LOGIN', stderr => \$psql_err);
+$node->psql('postgres', q[
+    CREATE FUNCTION reject_testUser3(port pgtle.clientauth_port_subset, status integer) RETURNS text AS $$
+        BEGIN
+            IF port.user_name = 'testUser3' THEN
+                RETURN 'testUser3 is not allowed to connect';
+            ELSE
+                RETURN '';
+            END IF;
+        END
+    $$ LANGUAGE plpgsql;]);
+$node->psql('postgres', qq[SELECT pgtle.register_feature('reject_testUser3', 'clientauth')]);
+$node->psql('postgres', 'select', extra_params => ['-U', 'testUser3'], stderr => \$psql_err);
+like($psql_err, qr/FATAL:  testUser3 is not allowed to connect/,
+    "clientauth function rejects testUser3");
+
+$node->append_conf('postgresql.conf', qq(pgtle.enable_clientauth = 'on'));
+$node->append_conf('postgresql.conf', qq(pgtle.clientauth_users_to_skip = 'testUser3'));
+$node->restart;
+
+$node->command_ok(
+    ['psql', '-U', 'testUser3', '-c', 'select;'],
+    "clientauth function does not reject testUser3 when testUser3 is in pgtle.clientauth_users_to_skip");
+### 17. Allow mixedCase in pgtle.clientauth_databases_to_skip
+$node->psql('postgres', 'CREATE DATABASE mixedCaseDb');
+$node->append_conf('postgresql.conf', qq(pgtle.clientauth_users_to_skip = ''));
+$node->append_conf('postgresql.conf', qq(pgtle.clientauth_databases_to_skip = ''));
+$node->psql('postgres', 'SELECT pg_reload_conf();');
+
+$node->psql('mixedCaseDb', 'select', extra_params => ['-U', 'testUser3'], stderr => \$psql_err);
+like($psql_err, qr/FATAL:  testUser3 is not allowed to connect/,
+    "clientauth function rejects testUser3");
+
+$node->append_conf('postgresql.conf', qq(pgtle.clientauth_databases_to_skip = 'mixedCaseDb'));
+$node->psql('postgres', 'SELECT pg_reload_conf();');
+
+$node->command_ok(
+    ['psql', '-U', 'testUser3', '-c', 'select;'],
+    "clientauth function does not reject testUser3 when database is in pgtle.clientauth_databases_to_skip");
+
 $node->psql('postgres', qq[SELECT pgtle.register_feature('reject_testuser', 'clientauth')], on_error_die => 1);
 # Create role with name "
 $node->psql('postgres', qq[CREATE ROLE """" LOGIN], on_error_die => 1);