2.1, being based on newer JAX-WS and JAXB standards and introducing new dependencies could cause some issues to make a migration from 2.0.x to 2.1 more than a "drop in" replacement. This page documents some of those issues.
Code generation
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changes
WS-Addressing types
JAX-WS 2.1 supports the WS-Addressing stuff right in the API's. Thus, WSDL's that take/return the EnpointReferenceType will now generate the JAX-WS 2.1 EndpointReference instead of the CXF proprietary type that was generated in CXF 2.0.x. There is a flag (-noAddressBinding) to wsdl2java to disable the new type mapping, but the generated code is then not jaxws compliant.
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