Fotiman - 2:48 pm on May 30, 2012 (gmt 0)
That looks correct to me (I see the Cache-Control and Expires headers in your response). The first thing I would suggest would be to empty Opera's cache, and then try it again. If you get the same results, then I'm sure Opera has some developer tools that allows you to view the request/responses, so I would check that to see that Opera is getting a 200/OK for each request (and is not getting a 304). I don't use Opera, so I can't offer much advice as to how to do this.