[Seaside] show active page after hitting isolated code

[radoslav hodnicak]

On Mon, 22 Feb 2010, Julian Fitzell wrote:

> You could subclass WAResponseGenerator and implement #pageExpired,
> then specify that generator in your application's configuration.
>
> If that doesn't do what you want, you should create your own Filter.

Well I've got that far too, but how do I know what's the "present"? In 
(very) old versions of seaside you got the message that your page expired 
and a 3 seconds refresh brought you back the the "present", i.e. a 
valid/unexpired page. I don't quite understand how to do that in 3.0

rado