Detector Rail moved by Piston doesn't update block below

Redstone Torch stays lit off after piston moved Detector Rail with Minecart away.

What I expected to happen was...:
Redstone Torch should get on again

What actually happened was...:
Redstone Torch stays of

Steps to Reproduce:
1. Build Machine seen in the screenshot
2. Place a Minecart on the Rail (The Torch placed on the block below the rail gets off)
3. Power one Piston (The Torches don't change state)

4. Place Block next to one of the torches and they update.

 

Edit:

As seen in the 2. & 3. Screenshot this also happens with Redstone and Redstone Lamps