diff --git a/privatemsg.module b/privatemsg.module
index ac72c850640666be35ade735594f72553819bd12..c63b4b1aa026521170534c5a67fb0c2bb3aa5c9b 100755
--- a/privatemsg.module
+++ b/privatemsg.module
@@ -545,7 +545,9 @@ function privatemsg_thread_load($thread_id, $account = NULL, $start = NULL, $use
         $conditions['account'] = $account;
       }
 
-      // #2033161 privatemsg_message_load_multiple will load all threads if empty
+      // If the $ids parameter is empty, privatemsg_message_load_multiple will
+      // load all threads.
+      // @see https://drupal.org/node/2033161
       $ids = $query->execute()->fetchCol();
       if (count($ids)) {
         $thread['messages'] = privatemsg_message_load_multiple($ids, $conditions);
diff --git a/privatemsg.test b/privatemsg.test
index 33cd2436941123fc3474bd7e9ca240f48e6a6464..5f987a90d3a134ffbaddb837560e80a0424d693b 100644
--- a/privatemsg.test
+++ b/privatemsg.test
@@ -85,6 +85,11 @@ class PrivatemsgTestCase extends PrivatemsgBaseTestCase {
     $subject = $this->randomName(20);
     $body = $this->randomName(50);
 
+    // Make sure that $no_recipient is involved in another thread to assert that
+    // no unrelated messages are displayed.
+    // @see https://drupal.org/node/2033161
+    $unrelated = privatemsg_new_thread(array($no_recipient), $subject, $body, array('author' => $author));
+
     $response = privatemsg_new_thread(array($recipient), $subject, $body, array('author' => $author));
 
     $this->drupalLogin($user_no_read_msg);