2007/10/25, Bryan Tong Minh bryan.tongminh@gmail.com:
- Changing the licensing on the derivative work to be compatible with
the original work, and inform the creator of the new work of the change and the reason why.
You can't legally do that. If you release a derivative work of a GFDL work under something different than the GFDL, you violate the terms of the license and your license terminates. So you commit copyright infringement. It does nto mean that your derivative automatically becomes GFDL. IANAL.
Actually, in this case I think we can - by stating it's public domain, the creator of the derived image is reneging on their copyright on the work. It is perfectly allowed to publish a public domain work under the GFDL (although it is not effective, because being in the public domain, people can copy it anyway). It would be different if they had put another license on it, but if they put it under PD or copyrightedfreeuse, I think putting it back under the GFDL would be unproblematic.