1. I started a Spring DM bundle with issue (ESB-950)
2. I uninstall the Spring DM bundle.
3. Shutdown ServiceMix.
4. Restart ServiceMix.
5. Error starting ActiveMQ, 14:20:40,222 | ERROR | ExtenderThread-9 | BrokerService | he.activemq.broker.BrokerService 496 | Failed to start ActiveMQ JMS Message Broker. Reason: java.lang.NullPointerException
I removed the data directory to fix it (bad).
Log file attached.
It looks like you might be hitting AMQ-2512 which I think should be fixed in the latest broker snapshot (5.3.0-fuse-01-SNAPSHOT).
As a short term workaround you could try and use the amq persistence adapter rather than kahadb.