diff --git a/modules/content_retriever/content_retriever.module b/modules/content_retriever/content_retriever.module
index 2326fe9d578c416b5babc81b6db8440fd3e43072..c5f488c00548b095a1e2e7e4438d4834fc5cc801 100644
--- a/modules/content_retriever/content_retriever.module
+++ b/modules/content_retriever/content_retriever.module
@@ -647,11 +647,21 @@ function content_retriever_preprocess_page(&$variables) {
 /**
  * Implementation of hook_nodeapi().
  * 
+ * Warn when editing retrieved nodes.
  * Delete the record from the content_retriever table when a node 
  * is deleted.
  */
 function content_retriever_nodeapi(&$node, $op, $teaser, $page) {
   switch ($op) {
+    case 'prepare':
+      // If this is a node that has been retrieved from a remote site, warn
+      // a user about to edit it that their edits are not safe and may be
+      // overwritten by future updates.
+      $content_retriever_nid = db_result(db_query("SELECT nid FROM {content_retriever} WHERE nid = %d", $node->nid));
+      if ($content_retriever_nid) {
+        drupal_set_message(t('This %type was originally retrieved from a remote site. Any changes you make here are liable to be overwritten when new content is fetched from the remote site.', array('%type' => node_get_types('name', $node))), 'warning');
+      }
+      break;
     case 'delete':
       // remove db row from content_retriever
       db_query('DELETE FROM {content_retriever} WHERE nid = %d', $node->nid);