I report this problem on Moodle Tracker,http://tracker.moodle.org/browse/MDL-12862.
Character encoding of mod/wiki/ewiki/ewiki.php is not correct.
Old version of ewiki.php was encoded by ISO-8859-1(Latin-1).
Newest version of ewiki.php is encoded by UTF-8, maybe.
Please check line 638, function ewiki_page_css_container().
An argument of strtr() is not the same as following strings;
. strtr($id, ' ./ --_!"§$%&()=?²³{[]}`+#*;:,<>| @µöäüÖÄÜߤ^°«»\'\\',
P.S. And please check End-Of-Line code, too.