Getting error with lazy loading via createQuery() followed by $em->flush()

Simple O-O relationship between \Entities\User and \Entities\Feed. Seems like there's a problem with not-yet lazy-loaded proxies and $em->flush().

<?php
namespace Entities;

/** @Entity @Table(name="users_debug") */
class User {
    /**
     * @Id @Column(type="integer")
     * @GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @OneToOne(targetEntity="Feed", mappedBy="User", cascade={"persist"})
     */
    private $Feed;

    public function getID() {
        return $this->id;
    }
    public function getFeed() {
        return $this->Feed;
    }
    public function setFeed($feed) {
        $this->Feed = $feed;
    }
}
?>

<?php
namespace Entities;

/**
 * @Entity @Table(name="feeds_debug")
 */
class Feed {
    /**
     * @Id @Column(type="integer")
     * @GeneratedValue(strategy="AUTO", allocationSize=1)
     */
    private $id;

     /**
     * @OneToOne(targetEntity="User", cascade={"persist"})
     * @JoinColumn(name="user_id", referencedColumnName="id")
     */
    private $User;

    function setID($value) {
        $this->id = $value;
    }
    function getID() {
        return $this->id;
    }
    function getUser() {
        return $this->User;
    }
    function setUser($user) {
        $this->User = $user;
    }
}


?>

Table-data

users_debug:
 id
 361

feeds_debug:
 id  | user_id
 461 |     361

Code:

$user = $em->createQuery("SELECT u FROM Entities\User u WHERE u.id = 361")->getSingleResult();
print $user->getID(); // 361
// uncomment line below and it works
// print $user->getFeed()->getID();
$em->flush();

Error:
Warning: spl_object_hash() expects parameter 1 to be object, null given in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/UnitOfWork.php on line 1010
Warning: spl_object_hash() expects parameter 1 to be object, null given in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/UnitOfWork.php on line 566
Warning: ReflectionProperty::setValue() expects parameter 1 to be object, null given in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/UnitOfWork.php on line 575
Warning: get_class() expects parameter 1 to be object, null given in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/UnitOfWork.php on line 979
Fatal error: Uncaught exception 'ReflectionException' with message 'Class does not exist' in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadata.php:69
Stack trace:
#0 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadata.php(69): ReflectionClass->__construct(false)
#1 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php(247): Doctrine\ORM\Mapping\ClassMetadata->__construct(false)
#2 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php(177): Doctrine\ORM\Mapping\ClassMetadataFactory->_newClassMetadataInstance(false)
#3 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php(115): Doctrine\ORM\Mapping\ClassMetadataFactory->_loadMetadata(false)
#4 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/EntityManager.php(212): Doctrine\ORM\Mapping\ClassMetadataFactory->getMetadataFor(false)
#5 /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/UnitOfWork.php(979): Doctrine\ORM\EntityManager->getClassMetadata in /home/crotalus/src/Doctrine2-Dev/lib/Doctrine/ORM/Mapping/ClassMetadata.php on line 69

PostgreSQL log:
2009-10-10 16:32:58 CEST LOGG: execute pdo_stmt_000000000a283af8: SELECT u0_.id AS id0 FROM users_debug u0_ WHERE u0_.id = 361
2009-10-10 16:32:58 CEST LOGG: sats: DEALLOCATE pdo_stmt_000000000a283af8
2009-10-10 16:32:58 CEST LOGG: execute pdo_stmt_000000000a283af8: SELECT NEXTVAL('feeds_debug_id_seq')
2009-10-10 16:32:58 CEST LOGG: sats: DEALLOCATE pdo_stmt_000000000a283af8
2009-10-10 16:32:58 CEST LOGG: execute pdo_stmt_000000000a283af8: SELECT NEXTVAL('users_debug_id_seq')
2009-10-10 16:32:58 CEST LOGG: sats: DEALLOCATE pdo_stmt_000000000a283af8