Adding meta box to admin side of specific page template

Hey Mike,
Interesting question. There are two ways you can do this: you can either use javascript to show/hide the meta box based on the value of the page template, or you can only show it if the appropriate page template is selected. The former is probably the better way to go, because you could show/hide the meta box immediately as the page template dropdown changes. The latter will only show/hide after the post is saved. I was intrigued by that route all the same, so I threw some code together for it that I’m pretty sure will work:

add_action( 'after_setup_theme','trusted_page_sup' );
function trusted_page_sup() {
	if ( isset( $_GET['post'] ) )
		$post_id = $_GET['post'];
	elseif ( isset( $_POST['post_ID'] ) )
		$post_id = $_POST['post_ID'];
	else
		$post_id = get_the_ID();

	if ( ! $post_id )
		return;

	if ( 'page' != get_post_type( $post_id ) )
		return;

	if ( 'page-template.php' == get_post_meta( $post_id, '_wp_page_template', true ) ) {
		$tsuppliers2 = new Super_Custom_Post_Meta( 'page' );
		$tsuppliers2->add_meta_boxes( array(
			'id' => 'Contact-details',
			'context' => 'side',
			'priority'=> 'high',
			'post-type' => 'page',
			'fields' => array(
				'base' => array('type'=>'select', 'options' => array('vermont','cape town')),
				'Address' => array( 'type' => 'textarea' ),
				'Tel:' => array('type' => 'text'),
				'Fax' => array('type' => 'text'),
				'Email' => array('type' => 'text'),
				'Website' => array('type' => 'text'),
			)
		) );
	}
}

Good luck, and let me know how you make out!

Cheers,
Matt