diff --git a/include/boost/thread/win32/mutex.hpp b/include/boost/thread/win32/mutex.hpp
index eed19b34..28ae79f7 100644
--- a/include/boost/thread/win32/mutex.hpp
+++ b/include/boost/thread/win32/mutex.hpp
@@ -231,6 +231,10 @@ namespace boost
             
             void lock()
             {
+                if(locked())
+                {
+                    throw boost::lock_error();
+                }
                 m.lock();
                 is_locked=true;
             }
@@ -247,6 +251,10 @@ namespace boost
             
             void unlock()
             {
+                if(!locked())
+                {
+                    throw boost::lock_error();
+                }
                 m.unlock();
                 is_locked=false;
             }
diff --git a/include/boost/thread/win32/recursive_mutex.hpp b/include/boost/thread/win32/recursive_mutex.hpp
index 5dff4be4..51bcc5f4 100644
--- a/include/boost/thread/win32/recursive_mutex.hpp
+++ b/include/boost/thread/win32/recursive_mutex.hpp
@@ -211,6 +211,10 @@ namespace boost
             
             void lock()
             {
+                if(locked())
+                {
+                    throw boost::lock_error();
+                }
                 m.lock();
                 is_locked=true;
             }
@@ -227,6 +231,10 @@ namespace boost
             
             void unlock()
             {
+                if(!locked())
+                {
+                    throw boost::lock_error();
+                }
                 m.unlock();
                 is_locked=false;
             }
diff --git a/test/test_lock_concept.cpp b/test/test_lock_concept.cpp
index 0f2f0298..c8803133 100644
--- a/test/test_lock_concept.cpp
+++ b/test/test_lock_concept.cpp
@@ -134,8 +134,10 @@ boost::unit_test_framework::test_suite* init_unit_test_suite(int, char*[])
 
     add_tests_for_scoped_lock_concept<boost::mutex>(test);
     add_tests_for_scoped_lock_concept<boost::try_mutex>(test);
+    add_tests_for_scoped_lock_concept<boost::timed_mutex>(test);
     add_tests_for_scoped_lock_concept<boost::recursive_mutex>(test);
     add_tests_for_scoped_lock_concept<boost::recursive_try_mutex>(test);
+    add_tests_for_scoped_lock_concept<boost::recursive_timed_mutex>(test);
 
     add_tests_for_scoped_try_lock_concept<boost::try_mutex>(test);
     add_tests_for_scoped_try_lock_concept<boost::recursive_try_mutex>(test);