Just make sure that a navigation doesn't propagate the conversation (remember non-Faces requests don't, or use an s:link with propagation="none").
Thx for your reply, I will try your suggestion, although it won't be that easy since I'm using tomahawks panelNavigation.
But since the conversation doesn't explicitly end this way, won't the next conversation that starts on a different overview cause an error?
well, as long as the navigation item will take an f:param you can do it that way (see the Seam ref docs).
You can have more than one conversation running at once, you just can't have more than one active conversation!
The s:link tag with propagation="end" works, while the equivalent f:param tag at least sometimes doesn't.
I think I have to stick with the s:link...
Thanks for your hints, I must have missed that part in the docs ;)