derived work

[Andres Baravalle]

Hi,
I'm writing a very small applet for gnome that is derived from a Red
Hat applet released under GPL version 2.

What I have done is reading their code and writing a new application
that uses some lines of their code *and* a library (eggtrayicon) that
they are using. My application is not a fork of their; it is just a
small applet to show today's comics.

How should I state (in the copyright notice) that my work is derived
from their? is derived the correct technical world?

I have prepared this copyright notice, but I'm not sure if it is
correct:

# Copyright (C) 2004 Andres Baravalle
# This file is part of phpGrabComics.
# phpGrabComics is free software; you can redistribute it and/or
modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
 
# phpGrabComics is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
 
# You should have received a copy of the GNU General Public License
# along with phpGrabComics; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 USA
 
# This file is based on the Red Hat Network Panel Applet
# Copyright 1999-2002 Red Hat, Inc
# distributed under GPL version 2.

Thanks in advance,
   Andres