Whenever getClass().getResource() , getClassLoader().getResource() and the like are used in galaxy code, they are guaranteed to fail in a multi-classloader environment for user resources. This hasn't been discovered yet only because there were not many embedding scenarios tried out. The easiest and most robust solution is to pull ClassUtils from Mule's code and adapt it if needed, then replace all usages with it: http://dev.mulesource.com/docs/site/2.0.0-RC2-SNAPSHOT/xref/org/mule/util/ClassUtils.html Dan, this could also be the reason why childDelegation tweak was required for surefire.