diff --git a/mac/setfile.sh b/mac/setfile.sh
new file mode 100755
index 00000000..da5b990a
--- /dev/null
+++ b/mac/setfile.sh
@@ -0,0 +1,22 @@
+#!/bin/sh 
+
+# Shell script to be run on Mac OS X, which uses `SetFile' to set
+# up the appropriate file metadata so that you can run MPW and have
+# it build classic-Mac PuTTY.
+
+SETFILE=/Developer/Tools/SetFile
+
+# I want to be able to run this either from the `mac' subdirectory
+# or from the main `putty' source directory.
+if test -f mac_res.r -a -f ../putty.h; then
+  cd ..
+fi
+if test ! -f putty.h; then
+  echo 'putty.h not found.' >&2
+  echo 'This script should be run in the PuTTY source directory.' >&2
+  exit 1
+fi
+
+# Now we can assume we're in the main PuTTY source dir.
+find . -name .svn -prune -o -name '*.[chr]' -exec $SETFILE -t TEXT {} \;
+$SETFILE -t TEXT mac/mkputty.mpw