Rails can't be pushed by Sticky Pistons

I tried to push a rail (powered or not) with a sticky piston and it didn't work.

What I expected to happen was...:
Push back and forth the rail, without dropping it.

What actually happened was...:
The rail acted like bedrock, obsidian or any bloc that can't be pushed by a piston

Steps to Reproduce:
1. Place a sticky piston on ground
2. Place a lever behind it.
3. Place a rail in front of the piston
4. Activate the lever.
5. Say "OH there is a bug D: "