Jen and Vince: back together?

Are Jennifer Aniston and Vince Vaughn rekindling their romance? Some weekly magazines seem to think so. According to OK!, the former couple are spending a lot of quality time together, and Aniston even made all the arrangements for Vaughn's 37th birthday party. "When Courteney Cox and David Arquette threw a birthday party for Jennifer on the eve of her 38th birthday in February, Vince was there for her, and she wanted to be there for Vince," says a source. "Jennifer made all the arrangements for the dinner herself."