diff -ru maillog.old/maillog.module maillog/maillog.module
--- maillog.old/maillog.module	2011-04-01 15:27:40.000000000 -0500
+++ maillog/maillog.module	2011-04-01 15:29:47.000000000 -0500
@@ -326,11 +326,15 @@
   if (variable_get('maillog_log', TRUE)) {
     $record = new stdClass;
 
+    $to = $message['to'];
+    if (is_array($to))
+    	$to = implode(', ', $to);
+
     $record->header_message_id = isset($message['headers']['Message-ID']) ? $message['headers']['Message-ID'] : NULL;
     $record->subject = $message['subject'];
     $record->body = $message['body'];
     $record->header_from = isset($message['from']) ? $message['from'] : NULL;
-    $record->header_to = isset($message['to']) ? $message['to'] : NULL;
+    $record->header_to = isset($to) ? $to : NULL;
     $record->header_reply_to = isset($message['headers']['Reply-To']) ? $message['headers']['Reply-To'] : '';
     $record->header_all = serialize($message['headers']);
     $record->sent_date = time();