The Icon Question

[Nicu Buculei]

Diana Fong wrote:
> *note...the office icon...one with the cup, pen and pencil is a deriv of 
> the Tango svg.
> I didn't think it was a problem because we will be sharing and sharing 
> alike and attributing Tango along with it's naming scheme and 
> metaphors.  Though we should probably figure out how Tango would like to 
> be attributed...and if such things (as in the deriv of the office icon) 
> is permissible.

What license is used for the new icons? GPL?
I am not an expert, but I am not sure is OK to make a derivative of an 
icon licensed as CC Attribution Share-Alike and publish it as GPL.