Martin, after debugging through this, I don't think that's the problem. From what I understand, WeldServletLifecycle.BEAN_MANAGER_ATTRIBUTE_NAME was explicitly added to handle this case, where the bean manager is already booted (or in process of being booted). Weld Servlet should be looking at that bean manager alone.

I suspect this is what Listener.using(BeanManager) is meant for. However it seems like this attribute isn't being used currently.