diff --git a/nailgun-server/src/main/java/com/martiansoftware/nailgun/NGServer.java b/nailgun-server/src/main/java/com/martiansoftware/nailgun/NGServer.java
index 00051f2..aa5fe76 100644
--- a/nailgun-server/src/main/java/com/martiansoftware/nailgun/NGServer.java
+++ b/nailgun-server/src/main/java/com/martiansoftware/nailgun/NGServer.java
@@ -477,7 +477,7 @@ public void run() {
 
             // Only after this point nailgun server is ready to accept connections on all platforms.
             // test_ng.py on *nix relies on reading this line from stdout to start connecting to server.
-            out.println("NGServer "
+            err.println("NGServer "
                     + NGConstants.VERSION
                     + " started on "
                     + listeningAddress.toString()