Hi Francis,
I think I'm actually reporting a malformed response, it is Nginx that send "nginx/1.4.3" instead of something useful as "too many requests". I have tested it with Firefox and there is no doubt. Also tested it with a java HTTP client component, the same result. The status code received is correct (429), but not the message that comes with it.
I had just discovered the "error_page" directive after I sent the email, I will create it, thanks. It is easy to do it. But why doesn't nginx deliver a default HTML response for 429, as it does for 503 and other codes? Why the empty page? It would make more sense to deliver the typical simple response, and that we could customize it with "error_page" if we wanted something more special.
Brian