diff -ruN ZThread-2.3.2.orig/include/zthread/Guard.h ZThread-2.3.2/include/zthread/Guard.h
--- ZThread-2.3.2.orig/include/zthread/Guard.h	2005-03-13 03:10:09.000000000 +0100
+++ ZThread-2.3.2/include/zthread/Guard.h	2012-06-30 22:35:07.602750705 +0200
@@ -428,7 +428,7 @@
   template <class U, class V>
   Guard(Guard<U, V>& g) : LockHolder<LockType>(g) {
 
-    LockingPolicy::shareScope(*this, extract(g));
+    LockingPolicy::shareScope(*this, this->extract(g));
     
   }