diff --git a/standalone/linux/install-haskell-packages b/standalone/linux/install-haskell-packages
index 15b968c436..a8103b3860 100755
--- a/standalone/linux/install-haskell-packages
+++ b/standalone/linux/install-haskell-packages
@@ -94,4 +94,9 @@ install_pkgs () {
 }
 
 cabal update
+
+# Some packages fail to install in a non unicode locale.
+LANG=C.UTF-8
+export LANG
+
 install_pkgs