--- image.module	2011-02-03 11:23:02.000000000 +0200
+++ image.module	2011-02-03 11:24:28.000000000 +0200
@@ -867,7 +867,7 @@ function _image_build_derivatives($node,
     }
 
     if (!$status) {
-      drupal_set_message(t('Unable to create scaled %label image', array('%label' => $size['label'])), 'error');
+      drupal_set_message(t('Unable to create scaled %label image from node %nid - image path is %path', array('%label' => $size['label'], '%nid' => $node->nid, '%path' => $original_path)), 'error');
       return FALSE;
     }
     // Set standard file permissions for webserver-generated files