Penalties and Queuerules not working


using Asterisk 11.5.1 Queues with penalties are not working as described e.g. at “Asterisk: The Definintive Guide”.

What would I expect from the following configuration:
If a call arrives at the queue “some-queue” all members with penalty 2 or 3 should ring.
(No matter whether some phones are busy or just not answering)
15 seconds later: Phones with penalty 4 should ring too, along with 2 and 3.
25 seconds later: All phones with penalties 1 to 5 should ring.

What actually happens:
If a call arrives: Only penalty 2 phones ring.
15 seconds later: No change
25 seconds later: Only phones with penalty 1 ring.

Did anybody get this working?

penaltychange => 15,4,2
penaltychange => 25,5,1

same => n,Set(QUEUE_MIN_PENALTY=2) ; set minimum queue member penalty to be used
same => n,Set(QUEUE_MAX_PENALTY=3) ; set maximum queue member penalty we’ll use
same => n,Queue(some-queue,more_members)

member => SIP/162,1
member => SIP/407,2
member => SIP/228,3
member => SIP/263,4
member => SIP/199,5

May it be, that Penalties only work if queue members are either busy or not logged in to the queue?

Are Queuerules buggy by intention?