Subscription is not echo'ed in v5.7 hub-spoke network of brokers

I'm using Apache ServiceMix 4.5.3 with ActiveMQ 5.7 in it.

I have 3 nodes all with exactly same config (except karaf name and ActiveMQ
broker name - they are different):
- hub
- spoke1
- spoke2

spoke1 is connected to hub via duplex openwire network connector.
spoke2 is connected to hub via duplex openwire network connector.

spoke1--(duplex)-->hub<--(duplex)--spoke2

My goal: produce messages on spoke1 and consume on spoke2 with hub doing
store-and-forward.

The problem:
- messages pile-up on spoke1
- spoke1 doesn't see any subscribers for this queue
- hub sees a subscriber (spoke2), but apparently doesn't advertise himself
as subscriber to spoke1

I tried the following combinations:
1) reverse: make spoke2 produce messages and spoke1 consume - same thing,
doesn't work
2) produce on spoke(s) and consume on hub - works
3) produce on hub and consume on spoke(s) - works
4) produce on hub and one spoke, consume on another spoke - only hub's
messages are consumed
5) produce on one spoke, consume on hub and spoke - only hub consumes
messages, which is kind of expected

Summing-up: it looks like a configuration with consumer-broker and
producer-broker doesn't work for me if separated by another broker, which
consumer and producers are both connected to through duplex
networkconnector.

What may I be doing wrong? What additional information might be helpful to
troubleshoot the issue?

Thanks!