Allow skipping of regression tests not supported on windows.  This reduces noise in the regression test suite for py3k on Windows.
diff --git a/Lib/test/regrtest.py b/Lib/test/regrtest.py
index edfaa9a..f970404 100755
--- a/Lib/test/regrtest.py
+++ b/Lib/test/regrtest.py
@@ -892,6 +892,7 @@
         test_fork1
         test_epoll
         test_dbm_gnu
+        test_dbm_ndbm
         test_grp
         test_ioctl
         test_largefile