It's complicated, because the upstream API documentation is derived from
comments in the source code, using the gtk-doc documentation system used
by GTK+ and related libraries.
Can you find a list of people who contributed substantially to the
comments?
You'd have to license source code under the GFDL (in addition to other
licenses), which surely is not your goal.
I don't think that is necessary; there are ways around it.
--
Dr Richard Stallman
President, Free Software Foundation
51 Franklin St
Boston MA 02110
USA
www.fsf.org, www.gnu.org
Skype: No way! That's nonfree (freedom-denying) software.
Use free telephony http://directory.fsf.org/category/tel/