This is a Centurion Framework module (http://www.centurion-project.org)
This module will help website to not loose the SEO. It will store in BDD all old url (if admin change the slug, or a category change, ...) and make redirect to the new url.
- add the module to your project
- activate the module "redirect" in the file modules.ini
- implement the interface Redirect_Model_DbTable_Row_Interface, in row that you want to be watch by this module
- test unit