Custom post type: Create permalink from title automatically

Hello folks,

I created a custom post type in my own plugin with the following code:

register_post_type('immovation_object', array(
	'labels' => array(
		'name' => _x('Immobilien2', 'post type general name'),
		'singular_name' => _x('Immobilie', 'post type singular name'),
	),
	'description' => "Immovation by Aweos - Description...",
	'public' => true,
	'has_archive' => true,
	'revisions' => false,
	'rewrite' => array( 'slug' => 'iiii', 'with_front' => true),
	'menu_position' => 5,
	'capability_type' => 'immovation',
	'supports' => array(
		'custom-fields',
		'attachments',
		'title',
		'thumbnail',
		'author'
	)
));

When I try to create a new post from that post type andgive that new post a title, the permalink of that new post is created automatically as “/iiii//”.
However, I would like to insert the slug from a title automatically, so that the slug would be “/iiii/the-slugged-title”. How can I do that?