Parent drop-down not appearing for custom post type

I’m trying to create a custom post type that I can associate with parent posts (they are posts not pages). WordPress is version 3.0.1. I was hoping to see a list of posts in a parent post drop-down under Page-Attributes but all I get its an ‘Order’ field. Have I missed something vital?

register_post_type( 'mytest_post_type',
    array(
        'labels' => array(
                'name' => __( 'mytest Interviews' ),
                'singular_name' => __( 'mytest Interview' ),
                'add_new' => __( 'Add New' ),
                'add_new_item' => __( 'Add New mytest Interview' ),
                'edit' => __( 'Edit' ),
                'edit_item' => __( 'Edit mytest Interview' ),
                'new_item' => __( 'New mytest Int.' ),
                'view' => __( 'View mytest Inteview' ),
                'view_item' => __( 'View mytest Int.' ),
                'search_items' => __( 'Search mytest Interviews' ),
                'not_found' => __( 'No mytest Interviews found' ),
                'not_found_in_trash' => __( 'No mytest Interviews found in Trash' ),
                'parent' => __( 'Parent mytest Interview' ),

        ),
        'public' => true,
        'show_ui' => true,
        'hierarchical' => true,
        'query_var' => true,
        'supports' => array('title', 'editor', 'author','custom-fields','page-attributes'),

    )
);

Or is it not possible to create a new custom post type and have those new posts be children of existing posts?

thanks!

This works for me. Looking at the code, the dropdown only appears if the post type is hierarchical (which is true in your case), and if there are other posts of the same type in the database. So a post can not be a child of another post type (a regular post or page for example), and the first new post of a type will not show the dropdown menu.