diff --git a/doc/plugins/mdwn/discussion.mdwn b/doc/plugins/mdwn/discussion.mdwn
new file mode 100644
index 000000000..9ebf99b7e
--- /dev/null
+++ b/doc/plugins/mdwn/discussion.mdwn
@@ -0,0 +1,11 @@
+Unlike other format, ikiwiki is somehow depends
+on mdwn, since the underlay dir
+is written in mdwn.  If you want to disable mdwn,
+you need to overwrite the underlay
+dir (set underlaydir in ikiwiki.setup
+to your own underlay dir or replace underlay pages
+in your $SRC).
+
+Specially, the [[shortcut]] plugin is hardcoded to
+use shortcuts.mdwn.  So you need pay more care if
+you [[use shortcut without mdwn|shortcut/discussion]].
diff --git a/doc/plugins/shortcut/discussion.mdwn b/doc/plugins/shortcut/discussion.mdwn
new file mode 100644
index 000000000..770c95836
--- /dev/null
+++ b/doc/plugins/shortcut/discussion.mdwn
@@ -0,0 +1,27 @@
+The plugin depends on [[mdwn]].  If you have
+disabled [[mdwn]], to get [[shortcut]] work, you need
+commit in a shortcuts.ext (ext is `rcs|creole|html|txt|etc`),
+and edit/patch [[shortcut]].
+
+Maybe use the $default_pageext is better than hardcode .mdwn?
+
+<pre>
+--- shortcut.pm.orig    2009-02-12 02:05:22.000000000 -0600
++++ shortcut.pm 2009-02-12 04:41:30.000000000 -0600
+@@ -23,9 +23,9 @@
+        if (defined $config{srcdir}) {
+                # Preprocess the shortcuts page to get all the available shortcuts
+                # defined before other pages are rendered.
+-               my $srcfile=srcfile("shortcuts.mdwn", 1);
++               my $srcfile=srcfile("shortcuts.$config{default_pageext}", 1);
+                if (! defined $srcfile) {
+-                       error(gettext("shortcut plugin will not work without a shortcuts.mdwn"));
++                       error(gettext("shortcut plugin will not work without a shortcuts.$config{default_pageext}"));
+                }
+                IkiWiki::preprocess("shortcuts", "shortcuts", readfile($srcfile));
+        }
+</pre>
+
+--[[weakish]]
+
+