Has anyone pointed out that in the UK 999 is the emergency number (like 911 in the US). So "999 Request Denied" sounds like a public safety issue to someone who doesn't speak tech. Make it 998 if you must.
I think if someone is looking at HTTP codes and extrapolating THAT from the response then there are other issues. At that point we might as well worry about people in Atlanta, GA not being able to call their mechanic if there's a 404 page.
seized|2 years ago