Custom Headers option in functions.php

There are a couple of plugins for selecting custom headers (Unique Headers, Custom Header Extended) which say "It should be noted that in order to use this plugin the custom headers option must be enabled (by the theme)." and they reference this page: http://codex.wordpress.org/Custom_Headers.

Are Custom Headers enabled in Atahualpa? Since which version? I didn't see it in the functions.php for 3.8.3.

Just saw this post http://forum.bytesforall.com/showthr...aders+function of January 18, 2014, which, if referring to the same issue means that it doesn't, is that correct?

Can you tell me if it's just a matter of adding

add_theme_support( 'custom-header' );

to functions.php?

Thanks.