Detector rails not working uphill.

Detector rails worked downhill but not uphill, when a detector was activated while going uphil the powered rail connected to it did not activate,

*I expected the powered rail to activate like it does if you are going downhill.
The powered rail did not activate causing the cart to stop.

Steps to Reproduce:
1. have a 1 block high "bump."
2. Place a powered rail on top of that "bump"
3. place a detector rail on the block adjacent to the bump, but one block lower
4 place a railroad adjacent to the detector rail so that the railroad, the detector and the the powered rail all line up along one line.
5. place a minecraft on the railroad
6. push it and get in