diff -r 596adf14914c Lib/test/test_msilib.py
--- a/Lib/test/test_msilib.py	Sat Jun 11 23:04:35 2011 +0100
+++ b/Lib/test/test_msilib.py	Sun Jun 12 09:19:36 2011 +0800
@@ -3,6 +3,26 @@
 import os
 from test.support import run_unittest, import_module
 msilib = import_module('msilib')
+from test import support
+import datetime
+
+msilib = support.import_module('msilib')
+import msilib.schema
+
+
+LAST_PRINTED_DATE = datetime.datetime(2011, 5, 30, 10, 55, 56)
+
+def create_temp_db():
+    "Create a very simple database to open"
+    path = support.TESTFN + ".msi"
+    db = msilib.init_database(
+        path, msilib.schema, "Python Tests", "product_code", "1.0", "PSF")
+    db.Commit()
+    db = None
+    return path
+
+TEST_DB_PATH = create_temp_db()
+
 
 class Test_make_id(unittest.TestCase):
     #http://msdn.microsoft.com/en-us/library/aa369212(v=vs.85).aspx
@@ -39,8 +59,20 @@
             msilib.make_id(".s\x82o?*+rt"), "_.s_o___rt")
 
 
+class TestSummaryInformation(unittest.TestCase):
+
+    def tearDown(self):
+        self.db = None
+
+    def test_get_property_vt_empty(self):
+        self.db = msilib.OpenDatabase(TEST_DB_PATH, msilib.MSIDBOPEN_READONLY)
+        si = self.db.GetSummaryInformation(0)
+        self.assertEqual(si.GetProperty(msilib.PID_SECURITY), None)
+
+
 def test_main():
-    run_unittest(__name__)
+    support.run_unittest(__name__)
+    os.unlink(TEST_DB_PATH)
 
 if __name__ == '__main__':
     test_main()
diff -r 596adf14914c PC/_msi.c
--- a/PC/_msi.c	Sat Jun 11 23:04:35 2011 +0100
+++ b/PC/_msi.c	Sun Jun 12 09:19:36 2011 +0800
@@ -558,6 +558,9 @@
             if (sval != sbuf)
                 free(sval);
             return result;
+        case VT_EMPTY:
+            Py_INCREF(Py_None);
+            return Py_None;
     }
     PyErr_Format(PyExc_NotImplementedError, "result of type %d", type);
     return NULL;