another setup.py workaround for Windows with missing MSVC

CHANGES.txt

+Version 3.1.1 released XXXX-XX-XX
+
+* setup.py now has another workaround for Windows machines without
+  MSVC installed
+  http://bugs.python.org/issue7511
+
 Version 3.1.0 released 2013-02-21
 
 * Updated JSON conformance test suite

setup.py

@@ -35,4 +35,5 @@
 if sys.platform == 'win32' and sys.version_info > (2, 6):
    # 2.6's distutils.msvc9compiler can raise an IOError when failing to
    # find the compiler
+   # It can also raise ValueError http://bugs.python.org/issue7511
    ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError,
@@ -38,5 +39,5 @@
    ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError,
-                 IOError)
+                 IOError, ValueError)
 else:
    ext_errors = (CCompilerError, DistutilsExecError, DistutilsPlatformError)