when i entered in the end portal (in a server with 15w51b) i spawned in the void of the end

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What I expected to happen was...:
Describe what you thought should happen here
When i entered the portal I expected to be on the obsidian platform
What actually happened was...:
Describe what happened here
What actually happened was that i spawned into the void
Steps to Reproduce:
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2. ...
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