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Ticket #3082 details a fix to add a body to redirect pages. This seems like
an old patch, but only now is it biting me. I have an authentication scheme
like this:

class ApplicationController < ActionController::Base
  before_filter :check_authentication, :except => [:signin]
  def check_authentication
      return true if session[:user]
      session[:return_to] = request.request_uri if request.request_uri !~
      redirect_to(:controller => 'admin', :action => 'signin') # ****
      return false

The problem is that the redirect_to is not redirecting, it's giving me the
page I initially asked for with a link to the proposed redirect page. I must
be missing something -- I use code like this all the time.