You should specify extra jar archives that are part of your JAXB implementation and are not built into the J2SE implementation. Specified directories, jar or zip archives will appear in the test executing Java classpath.

Classes implementing newer versions of endorsed standards should be placed in JAR files in <java-home>\lib\endorsed on Win32, <java-home>/lib/endorsed on Solaris or Linux. The Java runtime environment will use classes in such JAR files to override the corresponding classes provided in the Java 2 Platform as shipped by Sun.
See http://java.sun.com/j2se/5.0/docs/guide/standards/ for details.

Use "Add" button to browse and add a path to direcotry, jar or zip archive to the list (java classpath).

Use "Remove" button to remove a path to direcotry, jar or zip archive from the list (java classpath).

Since specified directories, jar or zip archives will appear in the classpath list in the order in which they are specified in this list. You can control the order by moving entries up or down. Upper entries will appear in the classpath first.

For example, for Oracle's reference JAXB implementation, all the jars in the <JAXB-RI>/lib directory and those, which are built into the reference implementation J2SE, should be listed.