Consider this, from the GPL Faq:

In an object-oriented language such as Java, if I use a class that is GPL'ed without modifying, and subclass it, in what way does the GPL affect the larger program?
...
Subclassing is creating a derivative work. Therefore, the terms of the GPL affect the whole program where you create a subclass of a GPL'ed class.

It's these types of issues that really add to the confusion. Also see tilly's reply in Using GPL'd Perl Modules in Commercial Software. There is a lot of room here, and I think many companies will making "use" of it shortly.

In reply to Re: Re: Derivative Works and Perl Modules by Anonymous Monk
in thread Derivative Works and Perl Modules by Anonymous Monk

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