I think you need to change up something to break this plateau. I would either really intensify my exercise routine burn a lot more calories or rest from the exercise for a week and really reduce my calorie intake. I have done 1000 calorie per day for a week with no exercise and it seems to work. I am no expert though, but you can give it a try. The point is to make a change so your body will react.
Others play around with their Prot/Carb/Fat mix, you can try increasing your protein for a while to see how that makes your body react.
Also you don't mention how much water you are drinking, be sure to really drink A LOT of it.
Hang in there!
Weight Jan 10, 2011 = 175 pounds
Weight Oct 10, 2011 = 146
Ultimate weight goal = 140 pounds sometime before the end of 2011