Pier Fumagalli wrote:
> Helma van der Linden wrote:
> 
> >Guys,
> >
> >I usually keep away from licensing issues, but this time I'd like  
> >to know if it is done correctly. I'm looking at a project that is  
> >made up of several other open source projects, cocoon is one of  
> >them, another (sub)project is licensed under BSD.
> >
> >This project is licensed under GPL. It doesn't say that only their  
> >part is GPL and others are licensed differently. Looks like they  
> >included the entire Cocoon source tree with licensing files for all  
> >external jars used and they also left in the ASF license headers in  
> >the various files.
> >
> >Is this correct?
> 
> It definitely is... The ASF doesn't pose any whatsoever restriction  
> when its code is being re-distributed by a third party (you could  
> virtually "sell" the ASF sources, and noone would be able to stop you).

This plain language FAQ is helpful:
http://www.apache.org/foundation/licence-FAQ.html#WhatDoesItMEAN
and follow through to the preFAQ which has a good overview,
and of course the main page:
http://www.apache.org/licenses/

It worth being familiar with the principles and aims.

> In this particular case, the entire project you methion is GPL  
> licensed, thus, any modifications made to it will be (as well) have  
> to be GPLed. This will guarantee that whoever inherits any of the  
> files from that project will have to redistribute them using the same  
> license (in case of any modification).
> 
> The problem might arise for those willing to "modify" code based on  
> that project and re-publish those changes:
> 
> If they submit changes to (let's say) Cocoon's sources back to the  
> project you're mentioning. The person modifying those sources can  
> either choose to submit them back to us (the real source) or to the  
> project they downloaded (the distributor).
> 
> In the first case, we'll accept those modifications only if we can  
> make them our own (copyright is assigned and transfered to the ASF)  
> and   will include them (hopefully) in our next release.

Thanks for the excellent description. However, that
copyright part is not correct. This point is so important
that i am goingg to quote it directly:
http://www.apache.org/licenses/ at second paragraph:
"
These licenses help us achieve our goal of providing reliable
and long-lived software products through collaborative open source
software development. In all cases, contributors retain full rights
to use their original contributions for any other purpose outside
of Apache while providing the ASF and its projects the right to
distribute and build upon their work within Apache.
"

> In the second, those changes will be in the hands of the distributor  
> (and thus GPLed). There are two options, either the copyright of  
> those changes is transfered to the ASF by the distributor (and then  
> we'll follows what's described above) or they'll have to maintain  
> those patches themselves as we're not going to include GPL licensed  
> code in our repository...
> 
> I hope this clears it a little bit...
> 
>       Pier
>