Automatic ordering through orderBy in many-to-many relation definition issue

class User extends Doctrine_Record
{
	public function setTableDefinition()
	{
		$this->setTableName('core_users');
		
		$this->hasColumn('username', 'string', 64, array('notnull' => true));
		$this->hasColumn('password', 'string', 128, array('notnull' => true));
	}
	
	public function setUp()
	{
		$this->hasMany('Role as Roles', array('local' => 'id_user', 'foreign' => 'id_role', 'refClass' => 'UserRole', 'orderBy' => 'position'));
		$this->actAs('SoftDelete');
	}
}

class Role extends Doctrine_Record
{
	public function setTableDefinition()
	{
		$this->setTableName('core_roles');
		
		$this->hasColumn('name', 'string', 64);
	}
	
	public function setUp()
	{
		$this->hasMany('User as Users', array('local' => 'id_role', 'foreign' => 'id_user', 'refClass' => 'UserRole'));
		$this->hasMany('Role as Parents', array('local' => 'id_role_child', 'foreign' => 'id_role_parent', 'refClass' => 'RoleReference', 'orderBy' => 'position'));
		$this->hasMany('Role as Children', array('local' => 'id_role_parent', 'foreign' => 'id_role_child', 'refClass' => 'RoleReference'));
	}
}

class UserRole extends Doctrine_Record
{
	public function setTableDefinition()
	{
		$this->setTableName('core_users_roles');
		
		$this->hasColumn('id_user', 'integer', null, array('primary' => true));
		$this->hasColumn('id_role', 'integer', null, array('primary' => true));
		$this->hasColumn('position', 'integer', null, array('notnull' => true));
	}
	
	public function setUp()
	{
		$this->hasOne('User', array('local' => 'id_user', 'foreign' => 'id', 'onDelete' => 'CASCADE'));
		$this->hasOne('Role', array('local' => 'id_role', 'foreign' => 'id', 'onDelete' => 'CASCADE'));
	}
}

class RoleReference extends Doctrine_Record
{
	public function setTableDefinition()
	{
		$this->setTableName('core_roles_reference');
		
		$this->hasColumn('id_role_parent', 'integer', null, array('primary' => true));
		$this->hasColumn('id_role_child', 'integer', null, array('primary' => true));
		$this->hasColumn('position', 'integer', null, array('notnull' => true));
	}
	
	public function setUp()
	{
		$this->hasOne('Role as Parent', array('local' => 'id_role_parent', 'foreign' => 'id', 'onDelete' => 'CASCADE'));
		$this->hasOne('Role as Child', array('local' => 'id_role_child', 'foreign' => 'id', 'onDelete' => 'CASCADE'));
	}
}

$query = Doctrine_Query::create()
	->from('User u')
	->leftJoin('u.Roles r')
	->orderBy('username ASC')
	->execute();

SELECT `c`.`id` AS `c__id`, `c`.`username` AS `c__username`, `c`.`password` AS `c__password`, `c`.`deleted_at` AS `c__deleted_at`, `c2`.`id` AS `c2__id`, `c2`.`name` AS `c2__name` FROM `core_users` `c` LEFT JOIN `core_users_roles` `c3` ON (`c`.`id` = `c3`.`id_user`) LEFT JOIN `core_roles` `c2` ON `c2`.`id` = `c3`.`id_role` WHERE (`c`.`deleted_at` IS NULL) ORDER BY `c`.`username` ASC, position

$query = Doctrine_Query::create()
	->from('User u')
	->orderBy('username ASC');
	
$result = $query->execute();
foreach($result as $item)
{
	echo count($item->Roles);
}

SELECT `c`.`id` AS `c__id`, `c`.`name` AS `c__name`, `c2`.`id_user` AS `c2__id_user`, `c2`.`id_role` AS `c2__id_role`, `c2`.`position` AS `c2__position` FROM `core_roles` `c` LEFT JOIN `core_users_roles` `c2` ON `c`.`id` = `c2`.`id_role` WHERE (`c2`.`id_user` IN (?)) ORDER BY position