Alternative licenses for artwork

[Callum McKenzie <callum physics otago ac nz>]

I have some art-work for gnome-games (specifically the new SVG graphics
for gnibbles) that the author would like to license under the Creative
Commons Attribution License. On the face of it I can't see any problem
with putting this in a GPLed package, but not being a licensing guru I
thought I had better check if there were any potential pit-falls or any
objections.

The author made this artwork explicitly for gnibbles so we can assume
that the author is OK about the mix.

The license in question can be found at:

http://creativecommons.org/licenses/by/1.0/

or, for the long version:

http://creativecommons.org/licenses/by/1.0/legalcode

 - Callum