code: public List getChildsInAllGenerations(String label) {
  		if (label == null || label.equals(""))
  			return new ArrayList(0);
  		List ret = new ArrayList();
  		Iterator it = childs.iterator();
  		while (it.hasNext()) {
  			AbcNode abcn = (AbcNode) it.next();
  			if (abcn.getLabel().equals(label)) {
  				ret.add(abcn);
  			} else {
  				ret.addAll(abcn.getChildsInAllGenerations(label));
  			}
  		}
  		return ret;
  	}
docs: Look for child, grandchild, grand-grand-child having the requested label.
  When such one is found, doesn't continue search into his own childs.
  
  @param label