Shattered Kingdoms

I have heard that Counterstrike now counters flanking attacks, is that true? And if is true, what exactly constitutes a flanking attack? I'm assuming it covers circlestab and hamstring, but what about a cleave that is done after battle is initiated with the barbarian? Would it cover that too?

What changed in the last update was that you can now counterstrike backstabs and hamstrings (circle-stab can't be used to initiate combat, right?) regardless of what row the rogue is at. If the barbarian is already caught up in combat, he certainly can't counter anything.