"According to this article in french paper Liberation , during the debate on TV between the two candidates to the presidential elections in France, Wikipedia.fr was edited several times by a number of anonymous surfers, to reflect the erroneous assertions of candidate Nicolas Sarkozy concerning the type of nuclear plant that is about to be built in the near future in France, if he takes office.
"At 22:34, Ségolène Royal snaps at her opponent: "You will have to look it up again: the EPR is the third generation of nuclear power plants, not the fourth." One minute later, a web surfer based in Nancy pays a visit to the french version of Wikipedia, and edits the EPR page : "third generation" is changed to "fourth generation".
That was the beginnig of a partisan editing battle on Wikipedia. The history page can be found here. Meanwhile, the English version of the same page did not budge."