I have been trying to use the prehandler exception feature but it does not seem to work.
My handler code looks like this
this.prehandler_exception = "keepalive";
public void function preHandler (required Event)
{
if( not getPlugin("sessionStorage").exists("webuser") )
{
relocate(event.buildLink('main.login'));
}
}
public void function keepalive(required Event)
{
var rc = Event.getCollection();
event.renderData(type="plain",data="#now()#");
}