A new cookie never be accepted if an HTTPClient has the same expired cookie.

It seems that a new cookie never be accepted if an HTTPClient has the same expired cookie.

For example, if a cookie is configured to be expired within 5 seconds, the following
code prints received cookies in the first loop, but prints empty arrays in the second loop.

hc = HTTPClient.new
2.times do
  hc.get("http://localhost/books")
  p hc.cookies
  hc.post("http://localhost/books",
          '{"title":"hello","body":"world"}',
          "Content-Type"=>"application/json; charset=utf-8")
  p hc.cookies
  sleep 5
end

It's OK that the old cookie is expired, but the new cookie should be accepted, shouldn't it?