Redirected to http://localhost:3000/session/new

So I have a rails app 2.x app that works fine via the web, but when trying to perform a POST I keep getting "Redirected to http://localhost:3000/session/new Filter chain halted as [:require_user] rendered_or_redirected.". In my iPhone app, I can create a new session and sign-in via my iPhone app, but cannot POST to say the POSTS_Controller.

I have this in my code

Posts_Controller

before_filter :require_user, :only => [:create, :update, :destroy]


Application_Controller
# Filters added to this controller apply to all controllers in the application.
# Likewise, all the methods added will be available for all controllers.

class ApplicationController < ActionController::Base 
  include AuthenticatedSystem
  include Geokit::Geocoders

  helper :all # include all helpers, all the time
  #session :session_key => '_cwa_session_id' 


  #filter_parameter_logging :password

  # See ActionController::RequestForgeryProtection for details
  # Uncomment the :secret if you're not using the cookie session store
  protect_from_forgery # :secret => 'eejj7eded74769099999944a729b4f'     

  #filter_parameter_logging(:password)

  before_filter :login_from_cookie
  before_filter :find_user_interests 
  before_filter :find_user_posts

 protected         
  def find_user_interests
    @user_interests = cur_user ? cur_user.interesting_posts : [] 
    logger.debug "User interests hash: #{current_user.inspect}"
  end          

  def开发者_运维技巧 find_user_posts
    @user_posts = cur_user ? cur_user.posts : []
  end     

  def cur_user
     User.find(session[:user_id]) if session[:user_id]  
  end

  def require_user
    unless cur_user
      flash[:error] = "You must be logged in to do that."
      redirect_to '/session/new'
      return false
    end
  end

  geocode_ip_address

  def geokit
    @location = session[:geo_location]
  end

end

I have been working on this for 2 months and cannot figure out the issue. In my iPhone app I am using ObjectiveResource. I am sending over json and have "Mime::Type.register_alias "application/json", :json" set up on the rails side.

I am not a rails developer, but the before filter for require_user is unable to pass the cur_user test in that is cannot find :user_id in the session hash. Are you sure that you have a session that persists when using the iPhone? Are you using devise for authentication? Just for kicks, does it work if you manually pass the user_id as params?