Sending Content (Message Body) along with 304 Not Modified header

Solution 1:

There is no point to sending a message body with a 304 response. In fact, the HTTP specification says that the server must not do so. If you have one that is, it's misbehaving according to the spec.

From the HTTP Specification:

The 304 response MUST NOT contain a message-body, and thus is always terminated by the first empty line after the header fields.