Response.Redirect() questions and Menu Item ?

[rockdale]

I have 2 pages (page A and Page B) both can access from my asp:menu
control (set the menu.NavigateUrl ). On page B I have a button which
call response.redirect("a.aspx") to redirect to page A. page A will
show different controls if it comes from Page B button or from Menu
Item.

The problem is
I click the button on page B to get to Page A. Now if I click the Menu
Item on my mainmenu to get to page A, the page A does not even call
page_load function, looks like the page is cached at somewhere. and
page A show the wrong controls ( it should show the controls that as
it comes from menu item). If I refresh from IE, then, I can see the
page_load function is called and it show s the correct controls.

Any idea why this happened? has the page been cached at somewhere? How
do I solve it.

Thanks in advance
-rockdale