Starting with AMQ+AMQP 1.0+QPID Proton

Hello,

I'm Pablo, from the IT of the University of Murcia. I'm new to the Message
Queue Services and I've registered here to learn more about ActiveMQ
day-to-day activity.

Also, I've a question about mixing AMQP 1.0 Filters/Selectors. I don't know
how to make a selector for filtering the Priority of a message. I have a
cluster of 6 machines with 3 workers each. 2 are low-priority workers and
can do any video transcode work with any priority, and 1 reserved worker
with higher priority only for user-time transcoding.

I've seen these pages:

https://svn.apache.org/repos/asf/qpid/trunk/qpid/specs/apache-filters.xml#type-selector-filter
http://activemq.apache.org/amqp.html
https://cwiki.apache.org/confluence/display/ACTIVEMQ/AMQP

I can send and receive messages using AMQP URLs:

amqp://127.0.0.1/route

But I dont know how to set the paramers to active the selector/filters for
selecting only messages with priority=5 or priority>5 (examples), tried a
lot of combinations:

amqp://127.0.0.1/route?header.priority=5
amqp://127.0.0.1/route?header.priority%3E5
amqp://127.0.0.1/route?transport.transformer=jms&priority=E5
amqp://127.0.0.1/route?transport.transformer=jms&priority%3E5
amqp://127.0.0.1/route?transport.transformer=jms&header.priority=E5
amqp://127.0.0.1/route?transport.transformer=jms&header.priority%3E5
...

There is no examples on the wiki or documentation to achieve this, so any
help will be apreciated.

Thanks for your time,
best regards.