Another way to cut down on portion size in a restaurant is to use the appetizer plate (the small ones that are at the table when you are seated) as your dinner plate. Serve yourself enough to cover the surface of the appetizer plate, and if you are still hungry, then take 1/2 of the amount you took before. Portion control is a gateway to calorie counting. Another neat trick that I've heard of is to bag 1/2 of your entree as soon as it gets to the table. That way you've only got 1/2 of your entree to eat and it's not so much a battle of will anymore.
Good luck!