Default content-type header added on 304 in a reverse proxy configuration.

Hi,
I noticed that in a reverse proxy configuration, when the backend server
answers with a 304 status without a content-type header, apache1.3 adds
a content-type header set to default value taken from the configuration.
Apache2 doesn't.

Which is buggy? The former or the latter?
I think it's the former since the original content-type might have been
whatever.

Regards.

--
Federico Mennite