$NetBSD: patch-settings_xfce4-session.xml,v 1.2 2015/06/29 16:50:01 youri Exp $

Look for the right thunar binary.
--- settings/xfce4-session.xml.orig	2014-08-28 15:50:18.000000000 +0000
+++ settings/xfce4-session.xml
@@ -21,7 +21,7 @@
       </property>
       <property name="Client2_PerScreen" type="bool" value="false"/>
       <property name="Client3_Command" type="array">
-        <value type="string" value="Thunar"/>
+        <value type="string" value="thunar"/>
         <value type="string" value="--daemon"/>
       </property>
       <property name="Client3_PerScreen" type="bool" value="false"/>