Extension:CategoryTree 

Extension:CategoryTree http://www.mediawiki.org/wiki/Extension:CategoryTree

Installation 

To install the required files,

  1. Copy the CategoryTree directory into the extensions folder of your MediaWiki installation.

    rsync -vuaC /svn/mediawiki/CategoryTree extensions/
  2. Then add the following lines to your LocalSettings.php file (near the end):

    # Enable CategoryTree
    $wgUseAjax = true;
    require_once( 'extensions/CategoryTree/CategoryTree.php' );

documented on: 2007.04.18