WebApp Sec: How to prevent Internet Explorer from locally caching pages

[Adrian Caneva <acaneva () nexttech com ar>]

Hi,
Expiration headers seem to be ignored by Internet Explorer behind a Proxy 
server when using BACK / FORWARD buttons.
On Microsoft's Knowledge Base Article  234067 (HOWTO: Prevent Caching in 
Internet Explorer) I've found that in fact this can happen.
And I could verify that, behind a Proxy, IE (6.0, 5.5, 5.0) gets the page 
from local disk cache although Expire = -1 header should force it ask the 
web server for an updated version.
The only workaround I've found was to place dynamic pages in an https:// 
environment where (Pragma, no-cache) header prevents IE from storing in 
local cache the response.
Any better ideas ?

Thanks very much in advance.
Regards,

Adrian Caneva