The already running KIT-Proxies have moved to production by activating the host for the Web Proxy Auto-Discovery Protocol (WPAD) wpad.kit.edu; hosts within kit.edu automatically contact it to get the Proxy Auto-Config (PAC). By default, they get taught not to use a proxy - you have to manually configure a PAC to actually use a proxy; see the page Web-Proxy for a service description and instructions to configure your browser.
At the same time, leagcy WPAD entries wpad.uni-karlsruhe.de, wpad.ka.fzk.de and wpad.fzk.de have been made aliases for wpad.kit.edu; they now deliver the same configuration. Previously they announced a proxy for targets outside their respective domain; they no longer do! If you wish to further use a proxy (due to network access, to benefit from caching or to conceal your IP addess for increased privacy in the internet), you have to configure a PAC manually as advised above. Please point that out to your users.