I'm using the global exception strategy at this link
Global Catch Exception Strategy is not used
I use a ref to this in each of my flow footers and have also used defaultExceptionStrategy-ref="catchExceptionStrategy" as shown in the link. But this exception
org.mule.exception.DefaultSystemExceptionStrategy: Caught exception in Exception Strategy: null
java.util.ConcurrentModificationException
...
is not being caught by my global exception. My assumption was that this is a message exception and the flow refs would therefore direct it to the global catch. Also that the defaultExceptionStrategy-ref configuration would direct any other exceptions to the global catch.