diff --git a/helpers/make-cpio-doc b/helpers/make-cpio-doc
index 5186d4f41cf9b7be746e0e59f4ee620f32206e98..f0930f1bfc13dbf1afb05a3a90a068eee6d702c0 100644
--- a/helpers/make-cpio-doc
+++ b/helpers/make-cpio-doc
@@ -19,7 +19,7 @@ VERSION=1
 
 # cpio-doc is under GFDL but due to "invariant sections" is considered
 # problematic for Debian
-EXTERNAL='deb-src http://archive.ubuntu.com/ubuntu main multiverse
+EXTERNAL='deb-src http://archive.ubuntu.com/ubuntu $UPSTREAM multiverse'
 
 . ./config