Major Description
The IllegalArgumentException "Unknown namespace for jpa: " is being triggered in org.apache.aries.jpa.blueprint.impl.JpaNsHandler.getSchemaLocation.
The bundle I am deploying has several extension namespaces defined in the Blueprint XML. I don't have a minimal example that exhibits this problem but I might be able to create one if necessary.
I'm not sure why the JpaNsHandler is being passed a namespace that it can't handle. However all other implementations of NamespaceHandler that I have seen return null if they are passed a namespace they do not recognize. When I replaced the IllegalArgumentException with returning null the bundle successfully started.
This is related to ARIES-1403.