--- a/xml/config.rnc	Sun Jun 21 16:21:51 2015 +0200
+++ b/xml/config.rnc	Sat Aug 15 09:40:22 2015 +0200
@@ -28,7 +28,14 @@
 			element property {
 				attribute name { text },
 				text
-			}*
+			}*,
+			element tunnel {
+				element command { text },
+				element argument {
+					attribute type { "literal" | "host" | "port" | "env" | "dbProperty" }?,
+					text
+				}*
+			}?
 		}*,
 		
 		element defaultFormatter { text }?,