ORM exclute strange

[anonymous]

My models is:

class Type(models.Model):
    id = models.AutoField(primary_key=True)
    slug = models.SlugField(unique=True, max_length=10)
    title = models.CharField(max_length=20)
    weight = models.SmallIntegerField(default=0, db_index=True)

class Active(models.Model):
    post = models.ForeignKey(Post, related_name='activeposts')
    rubrica = models.ForeignKey(Rubrica, related_name='activeposts')
    type = models.ForeignKey(Type, related_name='activeposts')
    user_id = models.PositiveIntegerField()
    pub_date = models.DateTimeField(default=datetime.now)

Type.objects.filter(Q(activeposts__rubrica__pk=112) & \
   Q(activeposts__user_id__in=[1,2,3])). \
   annotate(count=Count('activeposts')).query.as_sql()

Result is correct:

('SELECT `doska_type`.`id`, `doska_type`.`slug`, 
`doska_type`.`weight`, COUNT(`doska_active_new`.`id`) AS `count` 
FROM `doska_type` LEFT OUTER JOIN `doska_active_new`
      ON (`doska_type`.`id` = `doska_active_new`.`type_id`)
WHERE (`doska_active_new`.`rubrica_id` = %s
   AND `doska_active_new`.`user_id` IN (%s, %s, %s))
GROUP BY `doska_type`.`id`
ORDER BY `doska_type`.`weight` ASC', (112, 1, 2, 3))

But

Type.objects.filter(Q(activeposts__rubrica__pk=112) & \
~Q(activeposts__user_id__in=[1,2,3])). \
annotate(count=Count('activeposts')).query.as_sql()

Result is not correct:

('SELECT `doska_type`.`id`, `doska_type`.`slug`, 
`doska_type`.`weight`, COUNT(`doska_active_new`.`id`) AS `count` 
FROM `doska_type` LEFT OUTER JOIN `doska_active_new`
   ON (`doska_type`.`id` = `doska_active_new`.`type_id`)
WHERE (`doska_active_new`.`rubrica_id` = %s
   AND NOT (`doska_type`.`id` IN (
      SELECT U1.`type_id` 
      FROM `doska_active_new` U1 
      WHERE U1.`user_id` IN (%s, %s, %s)))) 
GROUP BY `doska_type`.`id`
ORDER BY `doska_type`.`weight` ASC', (112, 1, 2, 3))

[Malcolm Tredinnick]

(Reformatted description to avoid lots of side-scrolling.)

[Malcolm Tredinnick]

Are you actually seeing incorrect results returned from the database? What do you think the problem is here? I'm having trouble understanding what the bug might be and the SQL looks correct to me.