Hmm, I had a similar trouble maybe 2 years ago, I will try to remember it. Somehow it was perhaps related to flagged and unflagged versions.
Please make sure you use the newest Pywiki version, send a piece of code and tell us which wiki do you speak about (I think Obama has to have an article approximately in all Wikipedias).
I use this occasion to tell everybody that Mr. Obama has a funny name because "Barack" in Hungarian means peach or apricot. :-)