Caching problems with Typo 5.0.2

Hi

I performed a clean install of 5.0.2 yesterday, created a few test posts
and
deleted them all. I’m using semi static caching and have clicked ‘Empty
Fragment Cache’ a few times. But, my homepage never updated and the Atom
feed returns one of the deleted posts.

When I hit my blog root, nginx just returns a 304 and the browser just
renders the ‘No posts found…’ page - the request never even makes it
as
far as the typo mongrel. I assumed typo would be setting the appropriate
response headers itself, but do I need to explicitly configure nginx too
(other than a simple proxy-pass)?

Many thanks

Paul