<?php
namespace test\ns1;

class Foo {
    function test1(Foo $x) {
        echo "ok\n";
    }
    function test2(\test\ns1\Foo $x) {
        echo "ok\n";
    }
    function test3(\Exception $x) {
        echo "ok\n";
    }
}

$foo = new Foo();
$ex = new \Exception();
$foo->test1($foo);
$foo->test2($foo);
$foo->test3($ex);
?>