Impossible to edit some comments

[dbitouze]

When moderators or administrators click on the icon to edit any of the comments of the page http://texnique.fr/osqa/questions/244/conflit-entre-lextension-e-french-et-la-classe-hitec, the usual text area is not displayed and, instead, only a plain text page containing the comment's text appears, with no way to edit it (and troubles with encoding BTW). At a first glance, no problem to edit questions or answers.

Maybe related to issue #33.