diff --git a/Lib/ctypes/test/test_wintypes.py b/Lib/ctypes/test/test_wintypes.py
--- a/Lib/ctypes/test/test_wintypes.py
+++ b/Lib/ctypes/test/test_wintypes.py
@@ -1,8 +1,7 @@
 import sys
 import unittest
 
-if not sys.platform.startswith('win'):
-    raise unittest.SkipTest('Windows-only test')
+# also work on POSIX
 
 from ctypes import *
 from ctypes import wintypes
diff --git a/Modules/_ctypes/cfield.c b/Modules/_ctypes/cfield.c
--- a/Modules/_ctypes/cfield.c
+++ b/Modules/_ctypes/cfield.c
@@ -691,7 +691,11 @@
     return PyLong_FromLong(val);
 }
 
-#ifdef MS_WIN32
+#ifndef MS_WIN32
+/* http://msdn.microsoft.com/en-us/library/cc237864.aspx */
+#define VARIANT_FALSE 0x0000
+#define VARIANT_TRUE 0xFFFF
+#endif
 /* short BOOL - VARIANT_BOOL */
 static PyObject *
 vBOOL_set(void *ptr, PyObject *value, Py_ssize_t size)
@@ -713,7 +717,6 @@
 {
     return PyBool_FromLong((long)*(short int *)ptr);
 }
-#endif
 
 #ifdef HAVE_C99_BOOL
 #define BOOL_TYPE _Bool
@@ -1576,8 +1579,8 @@
 #endif
 #ifdef MS_WIN32
     { 'X', BSTR_set, BSTR_get, &ffi_type_pointer},
+#endif
     { 'v', vBOOL_set, vBOOL_get, &ffi_type_sshort},
-#endif
 #if SIZEOF__BOOL == 1
     { '?', bool_set, bool_get, &ffi_type_uchar}, /* Also fallback for no native _Bool support */
 #elif SIZEOF__BOOL == SIZEOF_SHORT