It's official: This is what Friends are for. Jennifer Aniston will guest on the March 27 season finale of Courteney Cox's FX series Dirt, Variety reports. The actress formerly known as Rachel Green will play a rival of Cox's tabloid editor.... Who better than Dr. Quinn, Medicine Woman, to guest on a show called In Case of Emergency? Randolph Mantooth, you say? OK, but he just wasn't right for the part of David Arquette's mother. Instead, Jane Seymour has been tapped to appear in three episodes. Actually, come to think of it, Jane's not right for that part, either. I'm seeing Shirley Jones.