Apparently the idea of dating Sean Penn is so horrific even to Natalie Portman that she actually released a statement so people would think she wasn't dating him. Despite her denial, at least two tabloids think she is still making breakfast with him in the mornings or at least catching a cab at 3am. Natalie says "Sean Penn is a friend and colleague. The reports that we are romantically involved are completely untrue."
A couple of things about all of this. If it turns out Natalie and Sean really are a couple or in the future become a couple people will always call her a liar, so I hope she knows what she is doing and that this isn't some statement released by some lied to or uninformed publicist. Second, who uses the word colleague? It always cracks me up when actors do this. A colleague is someone you network with once a month at a cocktail mixer while making fun of other people doing the exact same thing you are doing. The whole colleague thing seems to be a bit pretentious if your colleague is making Spring Break 83 while you are finishing up work on Road Trip 13. The friend thing? Hey, if she wants to be his friend that's fine. He probably doesn't have many female friends because they know what a prick he has. The fact she is willing to be his friend says a lot for her standards or devotion to a higher being.