The handbrake is adjusted automatically on the Mondeo, but is not always that good. If you have drum brakes on the rear you can remove the drums and adjust up the rear brake shoes. If you have discs brakes on thr rear, you should check to see if the caliper levers are returning all the way back? if they are not you could have a sticking cable or a faulty caliper?
Most mondeo's have rear drums, so adjusting up the shoes will cure your problem
Gary
January 2006