diff --git a/cpukit/ChangeLog b/cpukit/ChangeLog
index 03cc73c532..a2cd16c2f4 100644
--- a/cpukit/ChangeLog
+++ b/cpukit/ChangeLog
@@ -1,5 +1,6 @@
 2010-06-14	Ralf Corsépius <ralf.corsepius@rtems.org>
 
+	* posix/include/rtems/posix/threadsup.h: Add extern "C".
 	* libnetworking/netinet/in_pcb.c:
 	Eliminate "ushort".
 	* libfs/src/pipe/fifo.c, libfs/src/pipe/pipe.h:
diff --git a/cpukit/posix/include/rtems/posix/threadsup.h b/cpukit/posix/include/rtems/posix/threadsup.h
index e0d5ce9132..cc3a87e99a 100644
--- a/cpukit/posix/include/rtems/posix/threadsup.h
+++ b/cpukit/posix/include/rtems/posix/threadsup.h
@@ -20,6 +20,10 @@
 #include <rtems/score/coresem.h>
 #include <rtems/score/tqdata.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /*!
  *  This defines the POSIX API support structure associated with
  *  each thread in a system with POSIX configured.
@@ -83,5 +87,9 @@ void _POSIX_Thread_Exit(
   void           *value_ptr
 );
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif
 /* end of include file */