2008/7/31 Mike Godwin <mgodwin(a)wikimedia.org>rg>:
How could you add SA, for example, without being the
original
licensor, for importing to Wikipedia? How could you subtract it
without being the original licensor(s), for importing to Knol?
As long as you put the author's credits, respecting in this way the
request of attribution, you can change the license for your derivative
works and this includes also adding a SA clause. At least this is what
I have ever believed.
Massimiliano