diff --git a/handlers/dup.in b/handlers/dup.in
index 3ffc6abbb0b81a4dbd0fd0ca5637ac2fc96c34d8..e3475b8103f2818e2f3a274626d90b4c402ede70 100644
--- a/handlers/dup.in
+++ b/handlers/dup.in
@@ -2,7 +2,7 @@
 # vim: set filetype=sh sw=3 sts=3 expandtab autoindent:
 #
 # duplicity script for backupninja
-# requires duplicity >= 0.4.4
+# requires duplicity >= 0.4.4, and >= 0.4.9 when using a custom tmpdir.
 #
 
 getconf options