Cro logging mangles shell display

[andinus]

A long running Cro application on the Internet usually ends up with terminal being in this state:

We have configured it to log to a file:

        after => [
                  Cro::HTTP::Log::File.new(
                      logs => open('http.log', :a),
                      errors => open('error.log', :a),
                  )
              ]

But Malformed request line: errors are logged to STDERR.