diff --git a/sandbox/run_2to3.sh b/sandbox/run_2to3.sh
index abd373f86..a8a557c09 100755
--- a/sandbox/run_2to3.sh
+++ b/sandbox/run_2to3.sh
@@ -1,6 +1,6 @@
 rm -f src/version.py # Prevent 2to3 from copying it, since py3k/src/version.py was probably written by root.
 rm -rf py3k
 mkdir py3k
-cp locale/ py3k/ -R
-cp plugins/ py3k/ -R # copy plugins data
+cp -R locale/ py3k/
+cp -R plugins/ py3k/ # copy plugins data
 python 2to3/run.py src/ plugins/ test/ scripts/* setup.py -wWno py3k -f all -f def_iteritems -f def_itervalues -f def_iterkeys -f reload "$@"