Index: image/image.module
===================================================================
RCS file: /cvs/drupal/contributions/modules/image/image.module,v
retrieving revision 1.197.2.3
diff -u -F^f -r1.197.2.3 image.module
--- image/image.module	23 Aug 2006 20:00:31 -0000	1.197.2.3
+++ image/image.module	29 Aug 2006 14:45:47 -0000
@@ -293,9 +293,11 @@ function image_load(&$node) {
   // special images
   if (empty($node->images['thumbnail'])) {
     $node->images['thumbnail'] = $node->images['_original'];
+    _image_build_derivatives($node);
   }
   if (empty($node->images['preview'])) {
     $node->images['preview'] = $node->images['_original'];
+    _image_build_derivatives($node);
   }
 }