AMQ_SCHEDULED_DELAY not respected after upgrade to activemq 5.10

Hi,

I've upgraded from activemq 5.8 to 5.10 and it seems that now all of the
sudden the AMQ_SCHEDULED_DELAY header is no longer respected and messages
get immediately re-delivered. schedulerSupport is enabled on my broker

I enabled the loggingBrokerPlugin and turned on debug logging and the
AMQ_SCHEDULED_DELAY property is being logged. so i know it is correctly
sent to activemq

I've attached my activemq.xml (copied from 5.8)

Does anyone have any idea why this is happening and or how I can remedy
this ?

--Jelmer