Because WebSphere's JAX-WS implementation is based on Axis2, there are issues when deploying Axis2 on WAS 7.0 (and presumably on WAS 6.1 with the Web Services feature pack installed) because of conflicts with the Axis2 classes used internally by WebSphere. To solve this, it is necessary to change the class loader policy of the Web module to parent-last. However, this is not sufficient because Axis2 creates additional class loaders for modules and services, and these are parent-first.
In particular, there is an issue with the addressing module because org.apache.axis2.handlers.addressing.AddressingInHandler is present both in the WebSphere runtime and the addressing module shipped with Axis2. Since the module class loader is parent-first (and the class is not present in the Web application class loader), it is WebSphere's version of the class that will be loaded. This results in the following exception:
java.lang.ClassCastException: org.apache.axis2.handlers.addressing.AddressingInHandler incompatible with org.apache.axis2.engine.Handler
As a workaround, IBM proposes  to add copies of the module files as JAR files to WEB-INF/lib. However, a simpler solution is to switch the module class loader to parent-last. This is made possible by
AXIS2-4349, which will be available in 1.5.5.
The different options to deploy Axis2 in WebSphere should be properly documented, i.e.  needs to be updated.