In the French and Indian War scenario, we can unlock Indian Tribes by joining an active unit of a specified size to a locked indian band. By hovering the mouse over the locked Indian Tribe, it states the size unit necessary to activate the tribe. I moved an active Indian band of the appropriate size to join a locked Indian band but the inactive unit did not activate. I have noticed French units of appropraite size will activate locked Indian tribes. So is this a bug or are friendly indian tribes of appropriate size incapable of activating other locked indian tribes?