It is my understanding that
SOA Using Java� Web Services (
amazon US) may be of some help as it may make it easier for you to understand Java-based web services in general.
However the book seems to deal with JAX-WS in the context of
Java SE 6 or Java EE 5.
The SCDJWS certifies you for JAX-RPC 1.1 (and XML 1.0, XML Schema,
SOAP 1.1, WSDL 1.1, WS BP1.0a, UDDI 2.04, JAXR 1.0, JAXP 1.2, JAXB 1.0, SAAJ 1.2,
Servlet 2.4,
EJB 2.1) in the context of J2EE 1.4 � these older specifications are quite a bit different.
So you would still have to cover the material presented in
J2EE Web Services (Richard Monson-Haefel) (aka RMH)Designing Web Services with the J2EETM 1.4 Platform JAX-RPC, SOAP, and XML Technologies (pdf) (Java Blueprints) for the certification and keep it separated in your head from the standards presented in
SOA Using Java� Web Services.