Is there any Ruby equivalent for Python's NLTK?

On the Wikipedia “List of natural language processing toolkits” http://en.wikipedia.org/wiki/List_of_natural_language_processing_toolkits .. AlchemyAPI Ruby SDKhttp://www.alchemyapi.com/tools/ seems to be the only one listed for Ruby ..

Addendum:

This Ruby-1.8 “Natural Language Processing (NLP) Software” by Masao Utiyama (last updated 2007) turned up after my original answer above: