:create_if_missing does not work (0.3.2)

[ferret@…]

require 'rubygems'
require 'ferret'

include Ferret

index = Index::Index.new(
  :path => '/tmp/ferret-test/',
  :auto_flush => true,
  :create_if_missing => true,
  :default_search_field => ['subject']
)

gives me the following exception:

/opt/local/lib/ruby/gems/1.8/gems/ferret-0.3.2/lib/ferret/store/fs_store.rb:41:in `initialize': There is no directory: /tmp/ferret-test/. Use create = true to create one (RuntimeError)