diff --git a/src/docker.js b/src/docker.js
index fb762dae8..e0419d222 100644
--- a/src/docker.js
+++ b/src/docker.js
@@ -303,6 +303,7 @@ async function createSubcontainer(app, name, cmd, options) {
     const { fqdn:dashboardFqdn } = await dashboard.getLocation();
 
     const stdEnv = [
+        'LANG=C.UTF-8',
         'CLOUDRON=1',
         'CLOUDRON_PROXY_IP=172.18.0.1',
         `CLOUDRON_APP_HOSTNAME=${app.id}`,