--- a/.emacs-my	Thu Nov 04 21:53:32 2010 +0200
+++ b/.emacs-my	Tue Nov 09 22:53:33 2010 +0200
@@ -509,7 +509,7 @@
   )
 
 (defun my-file-name-tmp-p (file)
-  (string-match "\\(^#.*#\\|~\\|\\.orig\\|\\.log\\)\\'" (file-name-nondirectory file)))
+  (string-match "\\(^#.*#\\|~\\|\\.orig\\|\\.log\\|^.?\\.diff\\)\\'" (file-name-nondirectory file)))
 
 (defun my-dired-flag-tmp-files ()
   "Flag all temporary files for deletion."