Squid seems to have a bug with Expires and Date headers: It fetches an object and caches the headers. The object expires, and Squid fetches it again. The object is unmodified, so Squid continues to use the cached object. However, it appears that it also continues to return the old Expires and Date headers, even though it seems to be using new values "under the hood". This will confuse downstream caches, won't it?
