diff --git a/ext/pdo_firebird/tests/payload_server.php b/ext/pdo_firebird/tests/payload_server.php
index a2d2df4b7b2d..168929f644d6 100644
--- a/ext/pdo_firebird/tests/payload_server.php
+++ b/ext/pdo_firebird/tests/payload_server.php
@@ -1,6 +1,6 @@
 <?php
 
-$socket = stream_socket_server("tcp://localhost:0", $errno, $errstr);
+$socket = stream_socket_server("tcp://127.0.0.1:0", $errno, $errstr);
 if (!$socket) {
     echo "Can't start server: $errstr ($errno)\n";
     exit(1);