redirect_to kills my session variable

Hi,

I'm trying to set a session variable in one action of
application_controller.rb, which is then accessed in a second action of
the same controller following a redirect.

Here's the code.

def cookie_test
  if cookies["cookie_test"].blank?
    render :template => "shared/cookies_required"
  else
    #redirect back to where the user came from
  end
end

protected

def cookies_required
  return true unless cookies["cookie_test"].blank?
  session[:return_to] = request.request_uri
  cookies["cookie_test"] = Time.now
  redirect_to :action => "cookie_test" and return false
end

The method 'cookies_required' is called first, which sets the session
variable 'session[:return_to]'.

I would like to be able to access this variable in the method
'cookie_test' following the redirect.

However, when I try to do so, it shows up as nil.

I tried replacing the session variable with a global variable and that
worked fine.
I also tried sending the 'request.request_uri' variable as a parameter
to the second action and that worked too.

But why is my session variable dying following the redirect??

Thanks in advance