OnSessionEnd actually doing anything?!

Question

i want to do something very simple: when session expires, automatically redirect to a login page.
onSessionEnd looks like the logical choice, but i wasn't able to make it do anything at all!
any example that can show this function can do stuff is welcome, i've tried a bunch of them already, nothing works.
<cfcomponent output="false">
    <cfset this.name="testApp" />
    <cfset this.sessionManagement = true />
    <cfset this.applicationTimeOut = CreateTimeSpan(0,0,0,20) />
    <cfset this.sessionTimeout = createTimeSpan(0,0,0,20) />
    <cfset this.clientManagement = true />
    <cffunction name="onSessionEnd" access="public" returntype="void" output="false">
        <cflocation url="login.cfm">
    </cffunction>
</cfcomponent>

Answer 1

Think through what you're suggesting.
A session times out after an inactivity people, so intrinsically doesn't (and can't!) happen as part of a request... because a request implies activity. To redirect a request... there needs to be a request being made. But there is no request being made when a session times out.
You cannot interact with the browser in onSessionEnd(), because onSessionEnd() isn't - by definition - connected to browser activity.
What you want to do is to redirect to the login page when the session starts, not when it ends. Intrinsically the request after a session has ended will start a new session... and the redirect to the login page.
Make sense?
Adam