I have the same problem. I added this code to functions.php:
function mysite_add_dashboard_widgets() {
if ( is_blog_admin() && current_user_can('my_custom_capability') )
wp_add_dashboard_widget( 'dashboard_right_now', __( 'Right Now' ), 'wp_dashboard_right_now' );
}
add_action('wp_dashboard_setup', 'mysite_add_dashboard_widgets' );
Now I just need to have them log in to the home page rather than the profile page