Last modified: 2006-10-31 13:29:42 UTC
Found error message below when clicking the plus sign.
404 Not Found:
The requested URL //wiki/index.php was not found on this server.
Apache/2.0.59 (Win32) PHP/5.1.6 SVN/1.4.0 DAV/2 Server at ... Port 80
CategoryTree version: 17312 (from svn.wikimedia.org)
MediaWiki version: 1.9alpha (17297)
Fixed on trunk in r17322. Bug is actually in MediaWiki's main ajax.js, adding an extra / to the URL.
On most web servers this won't make a difference, but I guess you've got a funny configuration.