Description:
------------
The README.namespace said "Note that using "new A" in namespace 
you can only create class from this namespace or internal PHP class, however using "new ::A" you are able to create any class from the global namespace."

But, the class defined in global scope isn't found.

Reproduce code:
---------------
<?php

namespace A;

class foobar {
    public function test() {
    }
}

new ::foobar();


Expected result:
----------------
No error.

Actual result:
--------------
Fatal error: Class 'foobar' not found