It has been some years since looking at this code but you're right. The reason org.apache.xml and other bits are excluded is they are things used by jboss aop internally. However there should be a '.' after the package names. It looks like a include should work, but that you are using the wrong format. Looking at https://svn.jboss.org/repos/jbossas/tags/JBPAPP_4_2_0_GA/aspects/src/resources/META-INF/jboss-service.xml (from jboss 4.2) to refresh my memory I think it should be:
<include name="org.apache.xmlbeans.impl.store.Xobj$SoapBodyXobj"/>
There should not be a '.class' at the end, and the separator is '.'.