Since you're receiving calls at a Business, you probably don't want to do the kind of stuff you'd do if you were being called at home. I think you'd want to be careful about embarassing your company or starting rumors.
So next time you receive a call, just tell the caller "The boss told all of us not to forward your calls to her, or else. And, gee, I'm sure you don't want me to get in trouble with my boss. So goodbye." click.