Lately I've been noticing that the rear brakes on my 2000 GTV have been locking up when on an incline at a stop light. The car does not roll as it should when I release the brakes. Tonight I checked the e-brake and pumped on the pedal numerous times with the rear of the car on jack stands and everything releases back to normal as it should. Can this problem occur only when I've been driving for a while and occur with higher temperatures of brakes calipers and fluid?? Has anyone here on the BB experienced this problem?