It seems like gettext only searches for locale information in /usr/share/locale, by default. I installed ikiwiki into /usr/local, therefore the locale information wasn't found. This patch fixes the issue:

    --- a/IkiWiki.pm
    +++ b/IkiWiki.pm
    @@ -1057,6 +1057,7 @@ sub gettext { #{{{
                                    $gettext_obj=undef;
                                    return shift;
                            }
    +                       $gettext_obj->dir("$installdir/share/locale/");
                    }
                    return $gettext_obj->get(shift);
            }

[[tag patch]]
-- [[ThomasBleher]]

> According to my testing, this patch makes ikiwiki's localisation fail for
> `LANG=fr_FR` when everything is installed to the default locations, 
> though `LANG=es_ES` works. I don't understand this behavior, especially
> since strace shows it successfully opening the file
> `/usr/share/locale/fr/LC_MESSAGES/ikiwiki.mo`.
> 
> (Also, it should check that $installdir is set before using it.)
> 
> --[[Joey]]
