Feedback on free software licence requested

[MJR]

Alex wrote:
The proviso above is definitely not GPL-compatible, so in that sense the
poster is correct (I would say it's an extra restriction to the GPL). I
*suspect* some might even treat it as a non-free licence - for example,
the QPL does roughly what you want (#3.b) and although the FSF consider
it a free licence, others don't.

I think you might be referring to debian? Well, there are a few nasties
in how the QPL interacts with some contract law and there's the ability
of the copyright holder to make licensees spend a lot of money defending
themselves in court, but fortunately most use of the QPL is scuppered
by misapplication of it or other practical problems. There's also a
strong argument for dual licensing, which is what QPL author Trolltech