Do not upgrade dynamic headers - help!

I upgraded to the new Dynamic Headers version on this site:

http://equinecisers.com/wordpress/

and the message I got was the following:


Fatal error: Call to undefined function show_media_header() in D:\Hosting\2781642\html\wordpress\wp-content\themes\atahualpa342\header.php on line 49

I tried to delete the plugin (which hadn't even been activated), to no avail. I even tried to restore the old header file. That didn't work either.

So if this happens to anyone, revert to the old version of Dynamic Headers until there's a reply to this post.