Skip any chapter at your own risk. The objectives cover a lot of ground. The problem is that some of the chapters cover more detail than the exam requires - however there is no easy way to draw the line between what is fundamental (to the exam) and what is "too detailed" (in regard to the exam).
After all that you probably will still have some weak spots concerning the Transformation API for XML in JAXP 1.2. It's a good idea to know how exactly you would apply an XSLT with JAXP 1.2 and what javax.xml.transform.Source, javax.xml.transform.sax.SAXSource, javax.xml.transform.dom.DOMSource, javax.xml.transform.stream.StreamSource, javax.xml.transform.Result, javax.xml.transform.sax.SAXResult, javax.xml.transform.dom.DOMResult, javax.xml.transform.stream.StreamResult are all about.
Some people rely more heavily on Mikalai Zaikin's SCDJWS Study Guide - but that usually only works if you have some Web services experience already. [ March 22, 2006: Message edited by: Peer Reynders ]