Warning: I'm no developer, just copied and pasted from work by a different person.
Hope it's OK. Regards
diff --git a/babel/messages/catalog.py b/babel/messages/catalog.py index 501763b..e26e8f0 100644 --- a/babel/messages/catalog.py +++ b/babel/messages/catalog.py @@ -349,7 +349,10 @@ class Catalog(object): else: headers.append(('Language-Team', self.language_team)) if self.locale is not None: + headers.append(('Language', str(self.locale))) headers.append(('Plural-Forms', self.plural_forms)) + else: + headers.append(('Language', 'LANGUAGE')) headers.append(('MIME-Version', '1.0')) headers.append(('Content-Type', 'text/plain; charset=%s' % self.charset))