Disaster Assistance Network

Category Imports

This book chapter contains terms used for import. To import terms, activate free tagging for a category, select a related page, enter terms separated by commas. You can import up to 255 characters at one time. After importing, disable free tagging and arrange hierarchy or related terms as needed.

As of June 2, 2007, there is no taxonomy import module for 5.1. I am watching the Taxonomy_XML module for progress, but sadly, there is none.
http://drupal.org/project/taxonomy_xml
http://drupal.org/node/104402