diff --git a/src/tools/common/template.py b/src/tools/common/template.py
index 8d02a182..5b147f20 100644
--- a/src/tools/common/template.py
+++ b/src/tools/common/template.py
@@ -219,7 +219,13 @@ class Renderer(object):
     def setLocale(self, locale_str):
         if locale_str == self._locale_str:
             return
-        locale = Locale.parse(locale_str)
+        try:
+            locale = Locale.parse(locale_str)
+        except ValueError as e:
+            log.warning(_(u"invalid locale value: {msg}").format(msg=e))
+            locale_str = self._locale_str = DEFAULT_LOCALE
+            locale = Locale.parse(locale_str)
+
         locale_str = unicode(locale)
         if locale_str != DEFAULT_LOCALE:
             try: