diff --git a/session_expire.module
index a652a7a..7f94417 100644
--- a/session_expire.module
+++ b/session_expire.module
@@ -62,7 +62,8 @@ function session_expire_settings() {
     '#title'         => t('Session types'),
     '#default_value' => variable_get(SESSION_EXPIRE_MODE, 0),
     '#options'       => array(
-      t('Anonymous'),
+      t('Only anonymous'),
+      t('Only authenticated'),
       t('Both anonymous and authenticated users'),
       ),
     '#description'   => t('Types of sessions to discard. This option indicates whether only anonymous users, or both anonymous and authenticated users are expired. Note that if you choose authenticated users, they will be logged off and have to login again after the "age" specified above.'),
@@ -113,8 +114,13 @@ function session_expire_cron() {
 
     // Check if we should delete anonymous only or both anonymous and authenticated users
     $mode = variable_get(SESSION_EXPIRE_MODE, 0);
-    if (!$mode) {
-      $query->condition('uid', '0', '=');
+    switch ($mode) {
+      case 0:
+        $query->condition('uid', '0', '=');
+        break;
+      case 1:
+        $query->condition('uid', '0', '<>');
+        break;
     }
 
     // $max_deletions is way to prevent clearing out a huge amount of sessions.