Declarative Authorization Problem!

authorization rules

authorization do
  role :admin do
    has_permission_on [:project, :ticket, :comment, :user], :to => [:index, :show, :new, :create, :edit, :update, :destroy]
  end

  role :moderator do
    has_permission_on :project, :to => []
    has_permission_on :project, :to => []
    has_permission_on :ticket, :to => [:destroy]
  end

  role :guest do
    has_permission_on :project, :to => [:index, :show]
    has_permission_on :ticket, :to => [:index, :show, :create]
    has_permission_on :comment, :to => [:new, :create]
  end
end

users table

create_table "users", :force => true do |t|
    t.string   "email",                                 :default => "", :null => false
    t.string   "encrypted_password",     :limit => 128, :default => "", :null => false
    t.string   "reset_password_token"
    t.datetime "reset_password_sent_at"
    t.datetime "remember_created_at"
    t.integer  "sign_in_count",                         :default => 0
    t.datetime "current_sign_in_at"
    t.datetime "last_sign_in_at"
    t.string   "current_sign_in_ip"
    t.string   "last_sign_in_ip"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.string   "role"
  end