Turning on tracing overall produces huge logs. Can you suggest a particular category or set of classes to trace?
From the deployers package name:
* http://anonsvn.jboss.org/repos/jbossas/projects/snowdrop/trunk/deployers/src/main/java/org/jboss/spring/deployers/
looks like you should filter "org.jboss.spring" -- probably can also add ".deployer" for more detailed log.
Or perhaps you could debug this few deployers, and potentially see why it gets called twice?
I'll do a quick check asap, trying to understand why it would trigger twice.