java version "1.3.1"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.3.1-b24)
Java HotSpot(TM) Client VM (build 1.3.1-b24, mixed mode)

While executing
  java -cp .:../build/xerces.jar xni.DocumentTracer xni/conditional.xml
I get Segmentation fault:

startDocument(systemId="xni/conditional.xml",encoding="UTF-8")
 doctypeDecl(rootElement="root",publicId=null,systemId="conditional.dtd")
 startDTD()
  startEntity(name="[dtd]",publicId=null,systemId="conditional.dtd",encoding="UTF-8")
   comment(text="<!ENTITY % condition \"INCLUDE\">")
   startConditional(type=CONDITIONAL_INCLUDE)
    startContentModel(elementName="root",type=TYPE_ANY)
    endContentModel()
Segmentation fault

It works correctly with jdk 1.3 b17.

See attachements.