diff --git a/example/future_then.cpp b/example/future_then.cpp
index 7dd48624..4cdcf999 100644
--- a/example/future_then.cpp
+++ b/example/future_then.cpp
@@ -19,7 +19,7 @@ int p1()
   return 123;
 }
 
-int p2(boost::future<int>& f)
+int p2(boost::future<int> f)
 {
   BOOST_THREAD_LOG << "<P2" << BOOST_THREAD_END_LOG;
   try
@@ -38,7 +38,7 @@ int p2(boost::future<int>& f)
   }
   BOOST_THREAD_LOG << "P2>" << BOOST_THREAD_END_LOG;
 }
-int p2s(boost::shared_future<int>& f)
+int p2s(boost::shared_future<int> f)
 {
   BOOST_THREAD_LOG << "<P2" << BOOST_THREAD_END_LOG;
   try
diff --git a/example/lambda_future.cpp b/example/lambda_future.cpp
index a4650d5c..b6a3a55d 100644
--- a/example/lambda_future.cpp
+++ b/example/lambda_future.cpp
@@ -33,7 +33,7 @@ int main()
     }
     {
       boost::future<int> f1 = boost::async(boost::launch::async, []() {return 123;});
-      boost::future<int> f2 = f1.then([](boost::future<int>& f)  {return 2*f.get(); });
+      boost::future<int> f2 = f1.then([](boost::future<int> f)  {return 2*f.get(); });
       int result = f2.get();
       BOOST_THREAD_LOG << "f2 " << result << BOOST_THREAD_END_LOG;
     }
diff --git a/example/tennis.cpp b/example/tennis.cpp
index babc67dd..0212f677 100644
--- a/example/tennis.cpp
+++ b/example/tennis.cpp
@@ -4,6 +4,9 @@
 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
+#undef BOOST_THREAD_VERSION
+#define BOOST_THREAD_VERSION 2
+
 #include <boost/thread/mutex.hpp>
 #include <boost/thread/condition.hpp>
 #include <boost/thread/thread_only.hpp>