My personal impressions on ActiveMQ:1) Unstable. The code (along with version numbers) changes very often to be propely tested.
We've just come off the back of a period of fairly intense development, you're right. Most of the functionality we need is there now; we're focussing mostly on stability going forward.
Right now we've a fairly complete test suite (TCK, unit tests and load tests) though we're working with customers to add more scenarious and deployment configurations to our automated testing. With messaging there are so many different scenarious, topologies and requirements customers come up with - so our primary focus going forward is to ensure we automatically test these to ensure ActiveMQ is rock solid.
2) Lack of clustering/distributed messaging capabilities. Server does not support sending messages to remote queues, distributed durable subscribtions.
I don't follow? We support a federated network of servers with local and remote destinations (both store and forward and distributed destinations) and distributed subscriptions and message flows. Is there a specific topology you don't think we support?
3) JMS API speculations. Destinations are created on the fly and cannot be properly managed.
This is actually a feature lots of customers & users like, not an issue :). We can create destinations on the fly without long and laborious initial administation. e.g. compare getting MQSeries setup to something like Rendezvous. Once destinations exist you can manage them - but there's no absolute reason to have to manually configure them first. See the next issue for how we can lock down destinations so only specific users can use certain destinations...
4) Lack of security. No way to setup access rights to destination.
While not as advanced yet as some of the commercial alternative's we've a Security Plugin
which can be used to implement fine grained security access to brokers and destinations.
e.g. we've a provider
which supports JASS to authenticate and JACC to authorize the user operations.
If you have different security infrastructure or requirements, its easy to drop in other providers.
I hope that helps give you a better idea of where we are today with ActiveMQ.
Enterprise Open Source