1 files changed, 18 insertions, 0 deletions
diff --git a/src/mailman/languages/manager.py b/src/mailman/languages/manager.py
index 7844bd87c..87b56dbda 100644
--- a/src/mailman/languages/manager.py
+++ b/src/mailman/languages/manager.py
@@ -24,8 +24,11 @@ __all__ = [
     'LanguageManager',
     ]
 
+
+from zope.component import getUtility
 from zope.interface import implementer
 
+from mailman.interfaces.configuration import ConfigurationUpdatedEvent
 from mailman.interfaces.languages import ILanguageManager
 from mailman.languages.language import Language
 
@@ -72,3 +75,18 @@ class LanguageManager:
     def clear(self):
         """See `ILanguageManager`."""
         self._languages.clear()
+
+
+
+def handle_ConfigurationUpdatedEvent(event):
+    if not isinstance(event, ConfigurationUpdatedEvent):
+        return
+    manager = getUtility(ILanguageManager)
+    for language in event.config.language_configs:
+        if language.enabled:
+            code = language.name.split('.')[1]
+            manager.add(code, language.charset, language.description)
+    # the default language must always be available.
+    assert event.config.mailman.default_language in manager, (
+        'system default language code not defined: {0}'.format(
+            event.config.mailman.default_language))