custom url for custom post type

I think this is the right forum for this question. I have a custom post type ‘Event’. In register_post_type() I’ve got

'rewrite' => array(
		'slug' => 'events'

which is fine. But I also want year/month/date to come after events/ in the url, to help with repeating events. Put these only show up for posts, not my custom post type. Anyone know how I can get these to show? (I don’t want them to show for pages, just posts & this Events type).

I was looking at the permalink_epmask item, but I don’t understand how to use this, even if it actually is what I want.