My 05 (automatic transmission)rolls backwards on hills when you left off the brake to accelerate. Shouldn't the brakes automaticly keep you from rolling backwards?

If you press the pedal.

Seriously though, if you have the feature that holds you on the hill (don't know if all models do), it lasts for several seconds only(not going to look up the exact time).

The SE does not have the Hill Accent Assist like the Off-Road model.

ascent

Even with the OR the hill start only works for a few seconds (not sure exact time). Then it'll deactivate and you tap the brake pedal again and it will hold again.