There seem to be problems when creating long-running conversations. In link using IE8 the cid doesnt appear. Somehow it is stripped or doesn't render correctly, and it causes some strange behaviour.
When trying to create a long running conversation by pushing an edit link for instance, we get a "Your session has timeout" exception.
We fixed this IE8 problem by telling Internet Explorer to emulate IE7 in pages.xml
I suggest you do the same until the bug is identified and fixed.