2012/9/26 Emmanuel Briot <briot@adacore.com>
> Ok, only pieces Nick would use would need an approval of you to change to GPL2 or later.

It *was* a GPL later, since it was GPL 3. Now, I do not know much about these, so I have
simply changed the text in the README to say GPL 2, which is fine with me.

We investigated it somewhat in the past. Note that you should make it "GPL v2 or later", not just GPL v2.
Like this, the code can be used by people who want GPL3 or use a license compatible with GPL 3, but also by people who use GPL 2 only.