Tested with IE 5.2.1 on Mac OS X 10.4...
Subcategory links are all stacked on each other in some weird way... ewww!
Non-functional [+] buttons appear, and simply show "loading..." when clicked.
Attaching screenshot.
Version: unspecified
Severity: normal
OS: Mac OS X 10.4
Platform: Macintosh
URL: http://en.wikipedia.org/wiki/Category:Programming_languages