there's not alot you can do realy these are the mains things you can do: 1,leave the handbrake off or on one notch put in gear a leave it like that over nigh 2,get some warm or hot water and throw it over the rear wheels hoping it will free up the calipers 3,get a new handbrake cable- usaly the warn handbrakes suffer more from freezing in the mornings 4,somw put WD40 around all the connections but WD40+Brakes dont realy go lol.