diff -upr modules.orig/feedapi_mapper/mappers/feedapi_mapper_node.inc modules/feedapi_mapper/mappers/feedapi_mapper_node.inc
--- modules.orig/feedapi_mapper/mappers/feedapi_mapper_node.inc	2009-04-20 06:31:04.000000000 -0700
+++ modules/feedapi_mapper/mappers/feedapi_mapper_node.inc	2009-06-28 01:03:30.000000000 -0700
@@ -23,6 +23,9 @@ function node_feedapi_mapper($op, $node,
     if (is_string($feed_element) || is_numeric($feed_element)) {
       $node->{$field_name} = $feed_element;
     }
+    if ($field_name == 'body') {
+      $node->teaser = node_teaser($node->body, isset($node->format) ? $node->format : NULL);
+    }
     return $node;
   }
 }