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function add_cat_tag_page() {
  add_meta_box('tagsdiv-post_tag', __('Page Tags'), 'post_tags_meta_box', 'page', 'side', 'low');
	register_taxonomy_for_object_type('post_tag','page');
	add_meta_box('categorydiv', __('Categories'), 'post_categories_meta_box','page','side','core');
	register_taxonomy_for_object_type('category','page');
}
add_action('admin_init','add_cat_tag_page');

function page_tag_cat_request($q) {
	if (isset($q['tag']) || isset($q['category']))
		$q['post_type'] = array('post','page');
	return $q;
}
add_filter('request','page_tag_cat_request');