Do you believe the doors frozen shut or that you've disconnected the cable that links the door handle to the door latch?
If it's just frozen, boil some water and pour along the door's seams or blow hot air along the edges of the door to melt any snow/ice that is keeping the door from opening.
I had doors freeze on me for the first tihis winter. Only in my instance, the doors were frozen with me INSIDE the car!!
I had to roll down the window and make a Dukes of Hazard / General Lee dismount. Not pretty.
Luckily the car was in my garage at that point and both doors thawed overnight. I was kind of distraught when it happened because I had forced both door hadles because of ice accumulation and thought I had accidently disconnected to the door-opening mechanism.
Anyway, good luck and keep us posted.