diff --git a/includes/client/comments.php b/includes/client/comments.php
index ab071c4..e33f230 100644
--- a/includes/client/comments.php
+++ b/includes/client/comments.php
@@ -62,7 +62,7 @@ function get_comment_actor_slug( $comment ) {
     if ( $comment->user_id !== '0' ) {
         return get_comment_user_actor_slug( $comment->user_id );
     } else {
-        return get_comment_email_actor_slug( $comment );
+        return get_comment_guest_actor_slug( $comment );
     }
 }
 
@@ -75,7 +75,7 @@ function get_comment_user_actor_slug( $user_id ) {
     }
 }
 
-function get_comment_email_actor_slug( $comment ) {
+function get_comment_guest_actor_slug( $comment ) {
     $email_address = $comment->comment_author_email;
     $url = $comment->comment_author_url;
     if ( empty( $url ) ) {
diff --git a/includes/server/actors.php b/includes/server/actors.php
index f8b6d24..a819725 100644
--- a/includes/server/actors.php
+++ b/includes/server/actors.php
@@ -258,7 +258,7 @@ function get_create_actor_query( $slug, $type, $email = null, $url = null, $name
 
 function upsert_commenter_actor( $email_address, $url = null, $name = null, $icon = null ) {
     global $wpdb;
-    $slug = email_address_to_slug( $email_address );
+    $slug = name_to_slug( $name );
     $existing = $wpdb->get_row( $wpdb->prepare(
         "SELECT * FROM {$wpdb->prefix}pterotype_actors WHERE slug = %s",
         $slug
@@ -284,8 +284,11 @@ function upsert_commenter_actor( $email_address, $url = null, $name = null, $ico
     return $slug;
 }
 
-function email_address_to_slug( $email_address ) {
-    $slug = str_replace( array( '@', '.'), '_', $email_address );
-    return preg_replace( '/[^a-zA-Z0-9-_]/', '', $slug );
+function name_to_slug( $name ) {
+    if ( ! $name ) {
+        return 'anonymous';
+    }
+    $slug = str_replace( array( '@', '.', ' '), '_', $name );
+    return strtolower( preg_replace( '/[^a-zA-Z0-9-_]/', '', $slug ) );
 }
 ?>