Major Description
POI depends on dom4j that in turn depends on the xml-apis jar for some XML-related interfaces that are nowadays a part of the JRE. Normally having such an extra jar around doesn't harm anything as normal class loaders will always use the classes provided by the JRE. However some application servers like JBoss allow applications to override javax.* interfaces, which causes all sorts of trouble. Thus it's better if we exclude the xml-apis dependency from Tika.