Cache headers do not work with Classic asp

Question

I use classic ASP (.asp pages) on IIS 7 server. I do not have access to the IIS server, so pretty much any configuration I have to do, I do it on my asp pages.

I am trying to add cache headers to my asp pages and somehow the browser doesn't seem to respect them. I get new copies of my webpages even though the Cache-Control header is set to 24 hours.

This is what I see when I check it on web-sniffer.net for my asp page.

Status: HTTP/1.1 200 OK
Cache-Control:  max-age=86400, must-revalidate,public
Content-Length: 9483    
Content-Type:   text/HTML   
Server: Microsoft-IIS/7.0   
Set-Cookie: ASPSESSIONIDCAADASDQ=FKMLGPOANDEAFLJOEBHLIPDH; path=/   
X-Powered-By:   ASP.NET 
Date:   Mon, 11 Oct 2010 07:15:14 GMT   
Connection: close

This is what I used in my ASP code

 Response.AddHeader "Cache-Control","max-age=86400, must-revalidate"