Powered rail duplication glitch

Powered rail duplication glitch

What I expected to happen was...:
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What actually happened was...:
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Steps to Reproduce:
1. Make the setup as shown on Picture 1 (2013-02-26_17.37.54.png)
2. Place the powered rail on the block where the is moving in and out.
3. You will end up with 2 rails.