--- mailcomment.module
+++ mailcomment.module
@@ -436,8 +436,10 @@
  *
  * To be invoked on mapping time.
  *
- * @param $batch
- *   The FeedsImportBatch object being mapped from.
+ * @param $source
+ *   The FeedsSource object being imported.
+ * @param $result
+ *   The FeedsParserResult object being mapped from.
  * @param $key
  *   The key specified in the $sources array in
  *   hook_feeds_parser_sources_alter().
@@ -448,8 +450,8 @@
  * @see hook_feeds_parser_sources_alter()
  * @see locale_feeds_get_source()
  */
-function mailcomment_source_get_source(FeedsImportBatch $batch, $key) {
-  $item = $batch->currentItem();
+function mailcomment_source_get_source($source, FeedsParserResult $result, $key) {
+  $item = $result->currentItem();
   $identifier = _mailcomment_get_signature(rawurldecode($item['origbody']));
   if (!$identifier) {
     // Failed to find signature in body -- replicate mailhandler functionality to find node->threading