diff --git a/include/boost/thread/win32/once.hpp b/include/boost/thread/win32/once.hpp
index d1a525de..b11be97a 100644
--- a/include/boost/thread/win32/once.hpp
+++ b/include/boost/thread/win32/once.hpp
@@ -94,9 +94,9 @@ namespace boost
             detail::int_to_string(win32::GetCurrentProcessId(), mutex_name + once_mutex_name_fixed_length + sizeof(void*)*2);
 
 #ifdef BOOST_NO_ANSI_APIS
-            return win32::CreateMutexW(NULL, 0, mutex_name);
+            return win32::CreateMutexW(0, 0, mutex_name);
 #else
-            return win32::CreateMutexA(NULL, 0, mutex_name);
+            return win32::CreateMutexA(0, 0, mutex_name);
 #endif
         }
 
diff --git a/include/boost/thread/win32/shared_mutex.hpp b/include/boost/thread/win32/shared_mutex.hpp
index 73cdc490..3b322b1f 100644
--- a/include/boost/thread/win32/shared_mutex.hpp
+++ b/include/boost/thread/win32/shared_mutex.hpp
@@ -57,12 +57,12 @@ namespace boost
         {
             if(old_state.exclusive_waiting)
             {
-                BOOST_VERIFY(detail::win32::ReleaseSemaphore(exclusive_sem,1,NULL)!=0);
+                BOOST_VERIFY(detail::win32::ReleaseSemaphore(exclusive_sem,1,0)!=0);
             }
                         
             if(old_state.shared_waiting || old_state.exclusive_waiting)
             {
-                BOOST_VERIFY(detail::win32::ReleaseSemaphore(unlock_sem,old_state.shared_waiting + (old_state.exclusive_waiting?1:0),NULL)!=0);
+                BOOST_VERIFY(detail::win32::ReleaseSemaphore(unlock_sem,old_state.shared_waiting + (old_state.exclusive_waiting?1:0),0)!=0);
             }
         }
         
@@ -215,7 +215,7 @@ namespace boost
                     {
                         if(old_state.upgrade)
                         {
-                            BOOST_VERIFY(detail::win32::ReleaseSemaphore(upgrade_sem,1,NULL)!=0);
+                            BOOST_VERIFY(detail::win32::ReleaseSemaphore(upgrade_sem,1,0)!=0);
                         }
                         else
                         {
diff --git a/include/boost/thread/win32/thread_primitives.hpp b/include/boost/thread/win32/thread_primitives.hpp
index c8d55d29..f8f66b15 100644
--- a/include/boost/thread/win32/thread_primitives.hpp
+++ b/include/boost/thread/win32/thread_primitives.hpp
@@ -181,9 +181,9 @@ namespace boost
             inline handle create_anonymous_semaphore(long initial_count,long max_count)
             {
 #if !defined(BOOST_NO_ANSI_APIS)  
-                handle const res=CreateSemaphoreA(NULL,initial_count,max_count,NULL);
+                handle const res=CreateSemaphoreA(0,initial_count,max_count,0);
 #else
-                handle const res=CreateSemaphoreW(NULL,initial_count,max_count,NULL);
+                handle const res=CreateSemaphoreW(0,initial_count,max_count,0);
 #endif               
                 if(!res)
                 {