Yes. Fiorano and SonicMQ are both standalone JMS implementations. I also
believe that you can also many of the JMS providers from the big vendors
on their own (at least for MQ Series) .

An open-source implementations which might work for you but didn't work
for us are ActiveMQ, JORAM, MantaRay.

ActiveMQ turned out to be pretty unreliable in clustered HA scenarios
and the support was very bad even though the company paid for it.

MantaRay seemed immature at that time, so it wasn't evaluated.

JORAM I believe is a good product, but was not evaluated because 'we
don't want no French products in our company'... oh well.

hope this helped a bit.

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