Problems with callback and namespaces

[ecow]

Hi,
I got a strange problem that I can't understand. This snippet:

<?php
namespace test;
require 'vendor/autoload.php';
use Respect\Rest\Router;


$r3 = new Router('/tools/test.php');
    $r3->get('/', function() {
        return array('v' => 2.0);
    })->accept( array( 'text/html' => array( 'myns\\Standard', 'htmlRenderer')));

namespace myns;
class Standard
{
        public static function htmlRenderer($data)
        {
            return 'OK';
        }
}

works on window with php 5.4 and fails (Fatal error: Function name must be a string ) in ubuntu with php 5.3.

If in ubuntu I change the line 67 in file request.php from:

$response = $proxyCallback($response);

to

$response = call_user_func($proxyCallback,$response);

it works!
The problem seams related to namespace because if I remove namespace it works in both environments.
Can someone figure why?

This is a great library!!! Thank you

UPDATE:

It seams that the problem is related to a change in php 5.4.:

$callback = array($object, 'methodName');
$callback(); // prior to PHP 5.4 you need call_user_func()

Is php 5.4 a requirement for Respect\Rest?

[nickl-]

@botk thank you for bringing this under our attention. =)