Registering user without firstname and lastname

Now I'm not sure about changes which I've done
in my Drupal, chamilo.module and Chamilo,
but (if the problem occurs) you can try to add this code:

case 'insert':
	$admin_access = user_access('administer chamilo');
	$connect_access = user_access('connect with own Chamilo account');
	$sync_access = user_access('sync users with Chamilo accounts');

	$params = array(
		'loginname' => $account->name,
			'firstname' => $edit['profile_name'],
			'lastname' => $edit['profile_surname'],
		'password' => $account->pass,

instead of:

case 'insert':
	$admin_access = user_access('administer chamilo');
	$connect_access = user_access('connect with own Chamilo account');
	$sync_access = user_access('sync users with Chamilo accounts');

	$params = array(
		'loginname' => $account->name,
		'password' => $account->pass,