--- simplenews_template.module	2009-01-31 20:32:48.000000000 +0000
+++ simplenews_template.module	2009-02-12 15:44:30.626064000 +0000
@@ -88,9 +88,10 @@
  */
 function _simplenews_template_mail_alter_simplenews_node(&$message) {
   // Setup newsletter data
-  $tid = reset($message['params']['context']['account']->tids);
-  if (!empty($message['params']['context']['account']->tids)) {
-    $tid = reset($message['params']['context']['account']->tids);
+  $tids = $message['params']['context']['account']->tids;
+  $tid = is_array($tids) ? reset($tids) : $tids;
+  if (!empty($tids)) {
+    $tid = is_array($tids) ? reset($tids) : $tids;
   } else {
     $tid = $message['params']['context']['newsletter']->tid;
   }