Strange building on hopper minecarts

I think you just pressed the key too long.

Jeffrey, no - it only happens on top of the minecarts 

Still happening in 1.6.0.6.

Cleaning up old tickets: This ticket has not been updated recently (~7 months+) so is being closed as Cannot Reproduce. If you feel this is still a valid issue and is affecting the most recent versions, then please comment, or create a new ticket following the Issue Guidelines.

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