Devise: how can I manually set a remember_user_token cookie?
===

I'm using devise 1.1.RC0 for user authentication in a rails 3.0.0 app. 

Due to a problem with this version of devise, and the fact that our login process takes place on a (secure) subdomain, when a user logs in, the `remember_user_token` cookie does not get set. This only happens in production where subdomains are involved: the app will correctly set a `remember_user_token` cookie when testing locally.

To get around this problem, I've adjusted my `user_sessions#create` action to set this `remember_user_token` manually:

      def create
        user = User.where("lower(email) = ?", params[:user][:email].downcase).first
        if user and user.valid_password?(params[:user][:password])
          sign_in(:user, user)
          current_user.remember_me = true if params[:user][:remember_me]
          #ensure remember_user_token is set
          if Rails.env.production?
            cookies.signed["remember_user_token"] = {
              :value => user.class.serialize_into_cookie(user),
              :expires => 3.months.from_now,
              :domain => ".app_name.com",
            }
          end
          if session[:return_to]
            redirect_to session[:return_to]
          else
            redirect_to root_path
          end
        else
          flash[:error] = "Login incorrect"
          render :action => 'new'
        end
      end 


This does set a `remember_user_token` cookie in production. From there, if I delete the session cookie using browser tools and then refresh the page, the session cookie pops back in and I remain logged in - which I assume is what the `remember_user_token` cookie is responsible for.

However, if I close the browser and restart my computer while logged in, I'm no longer logged in when I turn my computer back on and go to my app's url. 

**What's the correct way to set this `remember_user_token` cookie?** What I'm I missing? I'd appreciate any help. 

Here's my `session_store` initializer:

    if Rails.env.production?
      AppName::Application.config.session_store :cookie_store, :key => '_app_name_session', :domain => '.appname.com'
    else
      AppName::Application.config.session_store :cookie_store, :key => '_app_name_session'
    end

Here's the relevant code in my `User` model:

      devise :database_authenticatable, :registerable, 
             :recoverable, :rememberable, :trackable, :validatable

