Bad news... The changes are not working. I have corrected most of the problems, but things start to become ugly. The problem is that at multiple locations in the core Class.forName is used which forwards the call to the classloader of the core bundle that does not see the additional packages. Have a close look to my diff-file to check which changes were necessary to get things forward.
A small summary:
(1) Replace the component-xml by those found in the diff. The namespace is important for SCR.
(2) There cannot be two methods which the same name, but which an input output structure not corresponding to the SCR spec. Therefore, I had to introduce the class MultiException to get rid of the return type List<Exception> and remove the initialize(ClassLoader) method.
(3) The component-xml must not be located in the OSGI-INF folder. You can revert the last change.
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.
(2) Use the fragment approach.
We have to replace all "Class.ForName" calls!
How to proceed?