How to send an array with Net::HTTP.post_form()?

Question

There are some checkboxes in a form, so the post data is:

type: flowers
color[]: red
color[]: white
color[]: blue

My code is:

Net::HTTP.post_form(URI.parse("http://xxx"), { :type=>'flowers',
                                               'color[]'=>%w[red white blue] })

It seems there is something wrong with my code, that I can't get the correct response. What's the correct code?

---

Is it a BUG?

I found a report about this:

http://rubyforge.org/tracker/?func=detail&atid=1698&aid=10340&group_id=426

It is reported in 2007, but seems not fixed. In my ruby 1.8.7 source code:

def set_form_data(params, sep = '&')
  self.body = params.map {|k,v| "#{urlencode(k.to_s)}=#{urlencode(v.to_s)}" }.join(sep)
  self.content_type = 'application/x-www-form-urlencoded'
end