Index: sources/canbus/messageacknowmodel.h
===================================================================
diff -u -r1ec7b44e6d1d66460d2da943ff65f3c0c0755d8f -r805119c460b4a266d6401c8705f4427e7fbe270f
--- sources/canbus/messageacknowmodel.h	(.../messageacknowmodel.h)	(revision 1ec7b44e6d1d66460d2da943ff65f3c0c0755d8f)
+++ sources/canbus/messageacknowmodel.h	(.../messageacknowmodel.h)	(revision 805119c460b4a266d6401c8705f4427e7fbe270f)
@@ -22,6 +22,8 @@
 // Define
 #define _MessageAcknowModel Can::MessageAcknowModel::I()
 
+class tst_acknow;
+
 // namespace
 namespace Can {
 
@@ -37,6 +39,8 @@
 
     Q_OBJECT
 
+    friend class ::tst_acknow;
+
     const int   _interval = 1000; // in ms
     int         _timerId  = 0;
     quint8      _retry    = 5;
@@ -104,6 +108,7 @@
 {
     Q_OBJECT
 
+    friend class ::tst_acknow;
 
     typedef QHash<Sequence, Private::AcknowModel *> AcknowList;
     AcknowList  _acknowList;