Bjoern ,
I noticed this problem just after I upgraded the CAI .So first I tougth it migth be a version bug but obviously it’s not.It happens in one scenario.
In my case I need to give a warning message just before I switch the current page to another one.The problem happens at this point. As I know switchToPage method doesn’t changes the current subsession.So for your question , my answer is no , I don’t touch sessions explicitly.
One more info : I lookup a session variable (findSessionContext().lookup) before I switching.It looks irrelevant but maybe it is.