--- mrd6-0.9.6.orig/include/mrd/support/ptree.h	2007-03-21 09:51:27.000000000 +0100
+++ mrd6-0.9.6/include/mrd/support/ptree.h	2012-07-25 17:21:57.000000000 +0200
@@ -38,6 +38,7 @@
 #include <stdint.h>
 #include <algorithm>
 #include <mrd/log.h>
+using std::ptrdiff_t;
 
 /* Patricia nodes MUST derive from ptree_node */
 struct ptree_node {