A blocker is now, that the correct classloader must be forwarded to SmackConfiguration. From my point of view, we have only two options to solve this issue:
(1) Create a separate class that performs the config file parsing which can be instantiated with a classloader used for class loading.
After reading this section again: Are you talking about the config file parsing that is done by smack-core? Does smack-cores initialization by processing of org.jivesoftware.smack/smack-config.xml fail in OSGi? If so, this should be easily fixable by also adding a Declarative Service for smack-core.