macfsn should always be included, like exceptions and site.
diff --git a/Mac/Tools/macfreeze/macmodulefinder.py b/Mac/Tools/macfreeze/macmodulefinder.py
index e89b990..166942d 100644
--- a/Mac/Tools/macfreeze/macmodulefinder.py
+++ b/Mac/Tools/macfreeze/macmodulefinder.py
@@ -19,7 +19,7 @@
# Modules that must be included, and modules that need not be included
# (but are if they are found)
#
-MAC_INCLUDE_MODULES=['site', 'exceptions']
+MAC_INCLUDE_MODULES=['site', 'exceptions', 'macfsn']
MAC_MAYMISS_MODULES=['posix', 'os2', 'nt', 'ntpath', 'dos', 'dospath',
'win32api', 'ce',
'nturl2path', 'pwd', 'sitecustomize',