Rails - May 2006 - No luck with multiple before_filters

I''ve got these two lines set up in my controller
  before_filter :check_authentication
  before_filter :check_max_hands, :only => [ :play ]

Here''s the corresponding code for each
  def check_authentication
    unless session[:user] and authorize?(session[:user])
      session[:intended_action] = request.request_uri
      redirect_to :controller => ''user'', :action =>
''signin''
      return false
    end
  end

  def check_max_hands
    u = current_user
    if !u.account_type.unlimited? && u.hands_played_this_month
>u.account_type.hands
      redirect_to :controller => "user", :action =>
"upgrade"
    end
  end

current_user just does User.find params[:user]

With my code like that, I get
"Couldn''t find User without an ID"

If I try to do "return false unless check_authentication" at the
beginning of check_max_hands, I get
"Render and/or redirect were called multiple times in this action..."

I''m pulling my hair out here.  All I want is for it to check to see if
the user''s logged in.  If not, go to the login page.  If so, continue
processing requests.  What''s going on?

Pat