redirecting to login page on session expiration

i have two webfolders : webmail and app with WEB-INF and web.xml inside. just like any other web folder hierarchy.
I have index.jsp in webmail folder that directs to login.jsp authenticating session.
I have index.jsp in app folder that directs to [B]login1.jsp in webmail folder[/B].
url login.com points to index.jsp in webmail folder.
url login1.com points to index.jsp in app folder.(i have nothing in store in app folder apart from index.jsp) this url is a virtual domain.
Already it is written in code, on session expiration the user gets redirected to login.com by default. Now that I have two domains. If the user logs in login1.com after the session expiration he is redirected to [B]login.com[/B]. As it just happens with login.com in webmail.
[COLOR=Red]IS THERE ANY WAY THAT I CAN REDIRECT USER WHO LOGGED IN LOGIN2.COM TO AGAIN LOGIN2.COM(AS IT SHOULD BE) ON SESSION EXPIRATION.[/COLOR]

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