JAXB 2.02 may also be used separately as suggested by Kohsuke Kawaguchi.
The JAXB 2.0 implemenetation in JWSDP 2.0 or Project GlassFish is recommended if other web service APIs(the "integrated stack") are also used.
"The current release of Java Web Services Developer Pack, Version 2.0, contains the new JAX-WS 2.0 EA, JAXB 2.0 EA, and SAAJ 1.3 EA implementations, the "integrated stack" for Web services. These components are now available as FCS-quality releases in Project GlassFish. These three components represent a new architecture that establishes more logical relationships between Web services description, data binding, and SOAP attachment processing. The result is that deploying Web services with the integrated stack is easier, more efficient, and more reliable."