NYCPHP Meetup

[Gary Mort]

I'm planning on some major rewrites to an existing GPL application.

I'd say that of the application, I will be extending, enhancing, or 
changing between 30 and 60 % of the application, including the program 
name for compatible reasons(the two modules must be able to be run in 
the same master program simultaneously, so a lot of classes and 
functions need to be changed to differentiate them)

What is the best way to note my code and provide the proper credit?

The current header has the program name, filename, version, and 
identifcation information of the current author(all GPL).

My own tendency would be to place my header underneath the existing one, 
however the version information would be different, so I want to give 
prominent credit to the original author, while still maintaining 
identification information.

The current header is as follows:
//
// Copyright (C) 2006 Thomas Papin
// http://www.gnu.org/copyleft/gpl.html GNU/GPL

// This file is part of the AdsManager Component,
// a Joomla! Classifieds Component by Thomas Papin
// Email: thomas.papin at free.fr
//

I'm thinking the best course would be:

// Adsmanager Extended
// Based on:
//--------------
//
// Copyright (C) 2006 Thomas Papin
// http://www.gnu.org/copyleft/gpl.html GNU/GPL
// This file is part of the AdsManager Component,
// a Joomla! Classifieds Component by Thomas Papin
// Email: thomas.papin at free.fr
//--------------
// Changes and Extentions
// Copyright (C) 2007 Gary Mort
// http://www.gnu.org/copyleft/gpl.html GNU/GPL
// This file extends and enhances the AdsManager Component,
// it can be installed stand alone, or alongside AdsManager


But that looks confusing to me.  Should I just stick all my new text 
below the existing notice?

Obviously, throughout the program I can mark my changes to the code 
where appropriate.

Just wondering what is considered best/common practice.