Please forgive me if this question has been asked/reported before, I couldn't find anything on the list or faq that suggest a solution. I have just been asked by the our designer of a strange problem he observed. While he was working on some new template on 2 of our testing site, he notices that after he shift-reload a certain static html on one of the site (let's call it site A), if he is to open the same url in the second site (Site B), which of course has some different content, he would landed getting content of the same URL in site A. To demonstrate the problem, I have prepared the following url. Site A - http://mymail.kafai-green-v1.sme.outblaze.com/test.htm Site B - http://mymail.kafai-blue-v1.sme.outblaze.com/test.htm Step 1) Open 2 browser instant (or 2 tab) bring each url up. Note : Site A should give you the word 'green' while site B give you the word 'blue' Step 2) shift-reload site A, then go to site B and reload (without shift). >From what I see here I landed with the word 'green' show up on Site B. (Note, if you can not replicate the problem with a browser, try these telnet command) Step 1 - telnet mymail.kafai-green-v1.sme.outblaze.com 80 GET /test.htm HTTP/1.0 Host: mail.kafai-green-v1.sme.outblaze.com Pragma: no-cache telnet mymail.kafai-blue-v1.sme.outblaze.com 80 GET /test.htm HTTP/1.0 Host: mail.kafai-blue-v1.sme.outblaze.com Pragma: no-cache (you should see the word green as html body for the first site and blue for the second site) Step 2 - telnet mymail.kafai-green-v1.sme.outblaze.com 80 GET /test.htm HTTP/1.0 Host: mail.kafai-green-v1.sme.outblaze.com Pragma: no-cache telnet mymail.kafai-blue-v1.sme.outblaze.com 80 GET /test.htm HTTP/1.0 Host: mail.kafai-blue-v1.sme.outblaze.com You should see 'green' after completing these 2 command. btw, the problem wouldn't work the other way around, I mean, if you load site B (Blue one) before Site A (green one) the problem wouldn't shows up. I'm running squid as http accelator in front of a apache installed in localhost, the 2 hosts are different vhost with different document root. I have upgraded squid to stable 10 yesterday and am still seeing this issue. Disabling squid would solve the problem. Any help would be much appreciated. Tor.