If you want to check it out, just go to http://www.univie.ac.at/rel_jap/an/ and ask for "Buddha" in the search box. You will see that among the results, there are several https links
Well, the SSL cert question is answered. Looks like you are on a University server in a subfolder so I would imagine they must have a SSL cert for the main domain. Also looks like you are on a wiki farm. http://www.univie.ac.at/rel_jap/ takes you to a landing page of other wikis.
How much control of the site do you have? Are you sharing one installation? How did you install your own custom skin?
Tom