As mentioned on Sun education web page, the only *official* prerequisite is that you need to have passed the SCJP certification.
The first sentence on that page states, I quote:
The Sun Certified Developer for Java Web Services certification exam is for developers who have been creating web services applications using Java technology components such as those supported by the Java Web Services Developer Pack and the Java 2, Enterprise Edition 1.4 platform.
Right, the verb "create" stands somewhere in there. It doesn't mean that you won't be able to pass the exam if you only learn web services through books and tutorials, just that you would increase your chances and credibility of being certified by putting your hands in the mud
For starters, I would definitely download the JWSDP 1.4, start looking at the examples and create new web services. There are tons of examples on the web that you can check out and learn from. How much time it takes to master the objectives heavily depends on how fast you manage to create new neuronal connections in your brain
[ January 18, 2005: Message edited by: Valentin Crettaz ]
4.2 Given a set of requirements for a Web service, such as transactional needs, and security requirements, design and develop Web service applications that use servlet-based endpoints and EJB based endpoints.
8.3 Given a scenario, implement J2EE based web service web-tier and/or EJB-tier basic security mechanisms, such as mutual authentication, SSL, and access control.
9.1 Describe the steps required to configure, package, and deploy J2EE Web services and service clients, including a description of the packaging formats, such as .ear, .war, .jar, deployment descriptor settings, the associated Web services description file, RPC mapping files, and service reference elements used for EJB and servlet endpoints.
However, familiarity with creating EJB Endpoints, the deployment structure of an enterprise application consisting of an EJB Endpoint and the usage of transaction and security attributes in an ejb-jar file etc.. are required for the exam.
[ January 20, 2005: Message edited by: Kiran Baireddy ]