diff --git a/debian/README.source b/debian/README.source
new file mode 100644
index 0000000..c9df8cd
--- /dev/null
+++ b/debian/README.source
@@ -0,0 +1,9 @@
+How to build xen-tools directly from the Mercurial repository?
+==============================================================
+
+$ hg clone http://noone.org/hg/xen-tools/
+$ cd xen-tools
+$ make orig-tar-gz
+$ debuild -i'^\.hg'
+
+ -- Axel Beckert <abe@debian.org>, Fri,  9 Apr 2010 02:06:24 +0200
diff --git a/debian/changelog b/debian/changelog
index 2b61137..37f62af 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -42,6 +42,8 @@ xen-tools (4.2~rc1-1) UNRELEASED; urgency=low
     - ${parm/?/pat[/str]} → echo | sed
     - echo -e → printf
     - read → read dummy
+  * Added a README.source explaining how to build xen-tools directly from
+    the Mercurial repository.
 
  -- Axel Beckert <abe@debian.org>  Fri, 09 Apr 2010 01:30:49 +0200