params in functional tests not sent to controller encoded

I'm not exactly sure at what layer this problem is happening, so I'll just describe the behavior. I have an action in my foo controller, bar:

def bar
  "123!@/#$%^" == params[:number]
end

and a spec (also tried with test_unit, same behavior):

it "should be equal" do
  post :bar, :number => "123!@/#$%^"
end

now, that failed, and complained that there was no route that matched what I was asking for. I then realized that another spec worked, where the param being sent was completely alphanumeric. So I tried:

it "should be equal"
  post :bar, :number => CGI::escape("123!@/#$%^")
end

And it worked! So the problem was the '/' being sent as part of the URL.

However, my code didn't work, because the param value was "still" escaped in the controller. I thought, am I crazy or doesn't rails unescape params for me? (been a rails developer for 4 years). Just to make sure I tried it in the browser, and I was right, rails does do the unescaping.

Also, aren't controller specs/tests supposed to never be at the http level? I'm not sending a url to the controller, I'm invoking it with some values... escaping, urls, etc, should never ben an issue, right?

Let me know if you'd like any more info. I can put together some example code of that's helpful.