code: protected void handleGreedyEntityProblem(WstxInputSource input)
          throws XMLStreamException
      {
          String top = mElementStack.isEmpty() ? "[ROOT]" : mElementStack.getTopElementDesc();
          throwParseError("Improper GE/element nesting: entity &"
                          +input.getEntityId()+" contains closing tag for <"+top+">");
      }
docs: This problem gets reported if an entity tries to expand to
  a close tag matching start tag that did not came from the same
  entity (but from parent).