GPL

[Alessandro Rubini]

> 1) Does the GPL apply to the GPL, that is can you create a 
> licence which is based upon GPL without violating the GPL ?

No:

   Copyright (C) 1989, 1991 Free Software Foundation, Inc.
                       59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   Everyone is permitted to copy and distribute verbatim copies
   of this license document, but changing it is not allowed.
 
> 2) Can you licence some software under two licences for instance, 
> could you write a program and offer it under both GPL and say the 
> BSD licence ?

You can leave the choice to each user. That's common practice.
 
> 3) If a program is under GPL does that bar it from including non-
> GPL code ?

Yes and no. You can't make a derivative work with more restrictions than those
of the GPL. On the other hand, you can't make one with less restrictions,
as that would be against the license terms of the original work.

There's nothing strange in that, in my opinion, but this has been the topic
of endless flame wars. I won't participate in any BSD vs. GPL debate.

> 4) If you had for instance some graphics which you wanted to 
> include with a software package which was under GPL, but didn't 
> want to release the graphics under GPL is there anyway you could 
> do it ?

If the graphics is external to the package, there's no problem (except
that that that stuff is proprietary, and this is a problem per se).
If it's linked in the libre program, you can't distribute it (think
for example of graphics data linked in the application in order to
draw frequent tiles or so).

If the graphics is in a separate file but physically part of the
distribution, I can't tell. In practice it makes the whole package
non-free, but I don't know what would lawyers think of that
aggregation.

If you are looking for loopholes in the GPL, please don't do that
here: talk with your lawyer instead. There's a lot of uncertainty on
the borderline between allowed and forbidden use; everything depends
on who is going to judge.

/alessandro