yup, sounds familiar.  one of the parking brakes on the EV was
getting stuck frequently, but would unstick if I forced it a 
bit.  Except for one day this winter; the day my wife was running late for
jury duty and one rear wheel on both the EV and Quantum was stuck solid.  
No amount of dragging the wheel forward and reverse would unstick it.
She was NOT happy.  The only way I could release it was to take off the 
wheel and rap the drum with a mallet.  Had to do it with two cars.

It had rained on the way home the night before and the temps dropped into the
teens that night.  I learned my lesson that day!

rob