Index: nat.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/nat/nat.module,v
retrieving revision 1.34.2.28.2.18
diff -u -p -r1.34.2.28.2.18 nat.module
--- nat.module	25 Jan 2011 10:33:18 -0000	1.34.2.28.2.18
+++ nat.module	26 Jan 2011 17:29:46 -0000
@@ -511,7 +511,11 @@ function _nat_add_terms($node, $vids = a
     // $entities = entity_create_stub_entity('taxonomy_term', array(null, null, $term->vid));
     $entities = array();
 
-    $terms_saved[] = _nat_save_term($node, $hierarchy, $term, $entities, $fields);
+    // $term_saved will be NULL if the term name would have been empty.
+    $term_saved = _nat_save_term($node, $hierarchy, $term, $entities, $fields);
+    if (!empty($term_saved)) {
+      $terms_saved[] = $term_saved;
+    }
   }
 
   return $terms_saved;
@@ -537,7 +541,10 @@ function _nat_update_terms($node) {
     // Load entity fields.
     $entities = entity_load('taxonomy_term', array($term->tid));
 
-    $terms_saved[] = _nat_save_term($node, $hierarchy, $term, $entities, $fields);
+    $term_saved = _nat_save_term($node, $hierarchy, $term, $entities, $fields);
+    if (!empty($term_saved)) {
+      $terms_saved[] = $term_saved;
+    }
   }
 
   return $terms_saved;
@@ -568,9 +575,13 @@ function _nat_save_term($node, $hierarch
     }
   }
 
-  taxonomy_term_save($term);
-
-  return $term;
+  if (!empty($term->name)) {
+    taxonomy_term_save($term);
+    return $term;
+  }
+  else {
+    return NULL;
+  }
 }
 
 /**