--- C:\boost\boost_1_47_0\boost\asio\detail\impl\socket_ops.ipp	2011-06-05 16:21:43.000000000 -0700
+++ C:\boost\boost_1_47_0_mod\boost\asio\detail\impl\socket_ops.ipp	2011-07-19 08:50:57.000000000 -0700
@@ -23,12 +23,13 @@
 #include <cstring>
 #include <cerrno>
 #include <new>
 #include <boost/asio/detail/socket_ops.hpp>
 #include <boost/asio/error.hpp>
 
+#include <boost/asio/detail/mutex.hpp>
 #include <boost/asio/detail/push_options.hpp>
 
 namespace boost {
 namespace asio {
 namespace detail {
 namespace socket_ops {
@@ -2771,18 +2772,16 @@
 #else
       sprintf(serv, "%u", ntohs(port));
 #endif
     }
     else
     {
-#if defined(BOOST_HAS_THREADS) && defined(BOOST_HAS_PTHREADS) \
-      && !defined(BOOST_ASIO_DISABLE_THREADS)
-      static ::pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
-      ::pthread_mutex_lock(&mutex);
-#endif // defined(BOOST_HAS_THREADS) && defined(BOOST_HAS_PTHREADS)
-       //   && !defined(BOOST_ASIO_DISABLE_THREADS)
+#if !defined(BOOST_WINDOWS)
+      static boost::asio::detail::mutex mutex;
+      boost::asio::detail::mutex::scoped_lock lock(mutex);
+#endif // !defined(BOOST_WINDOWS)
       servent* sptr = ::getservbyport(port, (flags & NI_DGRAM) ? "udp" : 0);
       if (sptr && sptr->s_name && sptr->s_name[0] != '\0')
       {
         gai_strcpy(serv, sptr->s_name, servlen);
       }
       else
@@ -2794,17 +2793,12 @@
 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) && !defined(UNDER_CE)
         sprintf_s(serv, servlen, "%u", ntohs(port));
 #else
         sprintf(serv, "%u", ntohs(port));
 #endif
       }
-#if defined(BOOST_HAS_THREADS) && defined(BOOST_HAS_PTHREADS) \
-      && !defined(BOOST_ASIO_DISABLE_THREADS)
-      ::pthread_mutex_unlock(&mutex);
-#endif // defined(BOOST_HAS_THREADS) && defined(BOOST_HAS_PTHREADS)
-       //   && !defined(BOOST_ASIO_DISABLE_THREADS)
     }
   }
 
   ec = boost::system::error_code();
   return ec;
 }