Does you require thorough knowledge of XML and related technologies. Like XSL, XPath, Xpointer, and so on, to clear the test.
It is hard to say whether those XML-related topics are required to clear the test, but it is better for you to understand XML, DOM, SAX, etc so that you can understand Web Services easlier, as it is highly related to Core XML technologies.
Besides these how much weightage was given in exam to java and xml, JAXP.
The distribution on Pure Java, Pure XML and Pure JAXP should be less than 30%, however, questions are usually mixed. For example, how did you classify a question asking on UDDI registry using Java Code?