code: @Override 
  	public int lastIndexOf(Object o, int index) {
  		int idx = getRealIndex(index);
  		return super.lastIndexOf(o, idx);
  	}
docs: Returns the index of the last occurrence of the specified element in this
  vector, searching backwards from index, or returns -1 if the element is
  not found.
  
  @param o
  the object to look for.
  @param index
  the index at which the element lookup should start; it can be a positive
  number, or a negative number that is smaller than the size of the vector;
  see {@link #getRealIndex(int)}.
  @see java.util.Vector#lastIndexOf(java.lang.Object, int)