Theme Activation Error

I am trying to use the gallery (https://www.smashingmagazine.com/2009/05/04/download-gallery-a-free-wordpress-theme/) theme
but when I activate the theme I get:

Fatal error: Call to undefined function wp_page_menu() in /home/a4066518/public_html/wp-content/themes/thematic/library/extensions/hooks-filters.php on line 62

What could be causing this?