Search for forums would also be great, or not every single post that looks promising ending on a 404.
Here the hack for delivering a correct json (again, this does not answer my question, I don't want to modify my php, there must be a way in construct 3 to deal with it)
<?php
header('Content-type: application/json');
$json = array();
$json['c2dictionary'] = true;
$json['data']['asd'] = '123';
echo json_encode($json);
?>