[SOLVED] Implementing WordPress custom headers via add_theme_support

Hi,
I have been trying to implement the new WP custom headers function as explained at the link below in order to use one of the various plugins (Unique Headers, Dynamic Headers, etc.) which enable one to put a custom header discreetly on individual page/posts. I have had no luck and I wonder if there is something about Atahaulpa that defeats this function. Thanks in advance for any help.
Andrew

http://codex.wordpress.org/Custom_Headers