LinkageError due to javax.activation not in kernel anymore

With the update of Karaf from 4.2.1 to 4.2.2 I found the following error:

Caused by: java.lang.LinkageError: loader constraint violation: when resolving method "javax.xml.soap.SOAPMessage.createAttachmentPart(Ljavax/activation/DataHandler;)Ljavax/xml/soap/AttachmentPart;" the class loader "<unnamed>" (instance of org.apache.felix.framework.BundleWiringImpl$BundleClassLoader@2febf41d, child of java.net.URLClassLoader@3fee9989) of the current class, com/sap/it/cxf/xi/XIUtils, and the class loader <bootstrap> for the method's defining class, javax/xml/soap/SOAPMessage, have different Class objects for the type javax/activation/DataHandler used in the signature

I think this came in with this change: https://issues.apache.org/jira/browse/KARAF-5989

Since the servicemix javax.activation bundle is not part of the framework bundle anymore, it has to load it from the jdk and it will not import it from the servicemix bundle (see change above).

Other bundles correctly importing javax.activation will get it from the servicemix bundle.

This can lead to the linkage error outlined above.