What I still do find disturbing is that you claim your
project to be GPL-ed.
The dual license scheme effectively allows any user to buy him/herself
out of his/her obligations under the GPL. The GPL itself does not AFAIK
allow for such a buy-out, so as far as I can see it just doesn't apply.
it can only be done by the user negotiating directly with Jules, who
holds the copyright and is therefore not bound by the GPL with respect
to his own code.
a user who does this is effectively negotiating a new license
agreement with the copyright holder. the GPL has nothing to say about
what the copyright holder may or may not do under such circumstances,
since its an agreement *between* the copyright holder and a user who
has agreed to use the GPL.
someone may or may not like that Jules is willing to offer non-GPL
licenses for JUCE, but he's completely free to do so, just as
TrollTech do (did?) for Qt.
i must say that the dual license nature of JUCE would be either the
first or second most compelling reason for me, as a GPL-using
developer, not to work with it. the idea that any work i contribute is
free to end up in a close-source product for which i will receive
neither compensation nor source code turns my stomach.
--p