diff --git a/cdist/conf/type/__cron/gencode-remote b/cdist/conf/type/__cron/gencode-remote
index 6f1feb90..e84cf66a 100644
--- a/cdist/conf/type/__cron/gencode-remote
+++ b/cdist/conf/type/__cron/gencode-remote
@@ -2,6 +2,7 @@
 #
 # 2011 Steven Armstrong (steven-cdist at armstrong.cc)
 # 2013      Nico Schottelius (nico-cdist at schottelius.org)
+# 2013      Thomas Oettli (otho at sfs.biz)
 #
 # This file is part of cdist.
 #
diff --git a/cdist/conf/type/__cron/manifest b/cdist/conf/type/__cron/manifest
new file mode 100644
index 00000000..9992df25
--- /dev/null
+++ b/cdist/conf/type/__cron/manifest
@@ -0,0 +1,24 @@
+#!/bin/sh
+#
+# 2013 Thomas Oettli (otho at sfs.biz)
+#
+# This file is part of cdist.
+#
+# cdist is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# cdist is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with cdist. If not, see <http://www.gnu.org/licenses/>.
+#
+
+if [ -f "$__object/parameter/raw" ] && [ -f "$__object/parameter/raw_command" ]; then
+    echo "ERROR: both raw and raw_command specified" >&2
+    exit 1
+fi