<?php // this is "arraytest.php"

class arraytest{
    private $array1 = array();
    public function __construct(){
        $this->array1[] = 'poodle';
    }
    public function getarray(){
        return $this->array1;
    }
}

class dododo{
   public $poop;
   public function __construct(){
        $poop = new arraytest();
    }
    public function foo()
    {echo 'bar';}
}

?>

<?php // this is page 1
require_once('arraytest.php');
session_start();
$bob = new dododo();
$_SESSION['bob'] = serialize($bob);
?>

<?php // this is page 2
require_once('arraytest.php');
session_start();
$bob = unserialize($_SESSION['bob']);
$bob->foo();
print_r($bob->poop->getarray()); // This generates an error.
?>

public function __construct(){
        $this->poop = new arraytest();
    }

public function __construct(){
        $this->poop = new arraytest();
    }