PHP 5.3 class type hint must be null error with namespaces

[tom@…]

Using xcache from svn trunk, once any class that uses class type hints in a method definition with null as the default value has been cached, php engine will throw a fatal error complaining that the default value is *not* null, if you "use" the same namespace as the one you are working in.

trivial example:

<?php
namespace My::NS;

use My::NS;

class A {
    public function test(A $obj=null) {
        var_dump($obj);
    }
}

actual result: "Fatal error: Default value for parameters with a class type hint can only be NULL in ..."

expected: no errors

[moo]

works for me in branches/1.3 (1.3.2-dev)