diff --git a/debian/rules b/debian/rules
index 5639f0e..a3b5d33 100755
--- a/debian/rules
+++ b/debian/rules
@@ -11,5 +11,5 @@ override_dh_auto_test:
 	# The tests make use of things like the history file, they need a dummy
 	# home directory.
 	mkdir test_homedir
-	HOME=$(shell pwd)/test_homedir dh_auto_test
+	LC_ALL=C HOME=$(shell pwd)/test_homedir dh_auto_test
 	rm -rf test_homedir