I have an array item with a French accent ([WIPDescription] => Recette Soupe à lOignon Sans Boeuf US). The data is being properly pulled from the database (mysql).
Another solution would be to use htmlentities or utf8_encode before using json_encode to pass the encoded char
like this:
$array = array('myvalue' => utf8_encode('ééàà'));
return json_encode($array);
Or using htmlentities :
$array = array('myvalue' => htmlentities('ééàà'));
return json_encode($array);