We have a strange problem in Safari. When the user logs out of our Web Application we expire the forms authentication with the following

 FormsAuthentication.SignOut();
 Session.Abandon();

This works fine in IE and Firefox (when the user hits the back button they are presented with a page expired message and are forced to login) but in Safari the last page the user was working on shows up. I tried many of the suggested thinks like setting the Response.Expires but nothing helps , Has anyone faced this problem ? Do u have any suggestion / workarounds ?

Thanks