Hi, I can't save the configuration of the Header. When I set all the configuration, and then I do click on "Save changes" I get this message:

Are you sure you want to do this?

Please try again.

I try it again, and the same.
I am using Atahualpa in another blog too, in the same server, but I don't get this message there.

What could be happen?

I though that I can changed that manually by editing the configuration code, but I don't know where I have to do it. If someone can guide me please.
Thanks.

Step one is to try disabling all your plugins

It seemed strange to me that was one of the plugins, since I have an English version of the blog, and with the same settings, plugin,etc, and have not had any problems with the other (the problemas was with my spanish version of my blog), but I've done what you said and the problem was fixed properly. Even when I re-activate the plugins, new options enabled functioned correctly.
I will consider to donate you because the Atahualpa theme is awesome!
Thank you very much!!!
Kind regards!