Description:
------------
If I call session_register with a string key that is in fact an integer, then it creates an entry in $_SESSION that is inaccessible using array indexes by a script. I think this is because the extension is adding the key to the array directly rather than using the hash APIs that convert string keys to integers where possible.


Reproduce code:
---------------
<?php
session_start();
session_register("123");
var_dump($_SESSION);
var_dump($_SESSION["123"]);
var_dump($_SESSION[123]);
?>


Actual result:
--------------
array(1) {
  ["123"]=>
  NULL
}

Notice: Undefined index:  123 in D:\ant.php on line 5
NULL

Notice: Undefined offset:  123 in D:\ant.php on line 6
NULL