Description:
------------
A stdClass shouldn't allow invalid proprieties names.

Numbers are not valid propriety name.

$object = new stdClass();
$object->0 = 1; //This is invalid
$object->{"\0"} = 1; //This is valid, why???

Test script:
---------------
<?php

$data = array( 'a', 'asdas' => 2312 );

print_r( (object) $data );

Expected result:
----------------
stdClass Object
(
    [asdas] => 2312
)

Actual result:
--------------
stdClass Object
(
    [0] => a
    [asdas] => 2312
)