Description:
------------
The bug is very simple, if you create an array with a custom key, if it detects that the key might be an integer, it will cast that key to an integer automatically.

(You have an example below)

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

$key1 = "00";
$key2 = "01";
$key3 = "11";


$array[$key1] = '';
$array[$key2] = '';
$array[$key3] = '';

foreach($array as $key => $value)
{
echo $key.':'.gettype($key).'<br />';
}

?>

Expected result:
----------------
00:string
01:string
11:string

Actual result:
--------------
00:string
01:string
11:integer