Listing blog posts in alphabetical order

Hi guys, I posted this questions awhile back and got this answer:
Add this code to functions.php:
add_filter(‘avia_blog_post_query’,’avia_modify_blog_post_query’);
function avia_modify_blog_post_query( $query)
{
$query[‘orderby’] = ‘name’;
$query[‘order’] = ‘ASC’;
return $query;
}

It worked before but now it not working.
Check out this page:
http://icf-pittsburgh.org/category/executive/
The names should be in alphabetical order. IDEALLY it would be nice to have them list in order of the LAST NAME
Can you guide me on how to get them listed in alpha order and as a bonus, can it be done by last name in alpha?
thanks for your help