diff --git a/test/files/script/utf8.scala b/test/files/script/utf8.scala
index 9fb7e9081..e0df6661b 100755
--- a/test/files/script/utf8.scala
+++ b/test/files/script/utf8.scala
@@ -18,6 +18,7 @@ then
     SOURCE=`cygpath --$format "$SOURCE"`;
 fi
 
+export LC_CTYPE=en_US.UTF-8
 exec scala -nocompdaemon "$SOURCE" "$@"
 !#