Handle ERROR_ALREADY_EXISTS.
diff --git a/Lib/bsddb/test/test_thread.py b/Lib/bsddb/test/test_thread.py
index 44e3e9c..61a0eb3 100644
--- a/Lib/bsddb/test/test_thread.py
+++ b/Lib/bsddb/test/test_thread.py
@@ -24,6 +24,12 @@
 except ImportError:
     have_threads = False
 
+try:
+    WindowsError
+except NameError:
+    class WindowsError(Exception):
+        pass
+
 import unittest
 from test_all import verbose
 
@@ -51,6 +57,8 @@
         self.homeDir = homeDir
         try:
             os.mkdir(homeDir)
+        except WindowsError, e:
+            if e.errno <> 183: raise # ERROR_ALREADY_EXISTS
         except OSError, e:
             if e.errno <> errno.EEXIST: raise
         self.env = db.DBEnv()