So, I have something that teleports @e[type=MinecartRideable,r=5] to a different location. If I am riding the minecart when it is teleported, the game renders me as being kicked out of the minecart, but if i press the sneak key or have the minecart ride over an activator rail, it boots me out where the minecart actually is. In addition, I cannot place blocks while in this desynced state. No pics because it would be extremely hard to demonstrate without a video.
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Seems to be fixed in 14w21b for minecarts
Bug is still there for boats!!!!

Seems to be fixed for 14w30c but please recheck
Duplicates: MC-11533
Is this still a concern in the current Minecraft version 1.7.5 / Launcher version 1.3.11 or later? If so, please update the affected versions in order to best aid Mojang ensuring bugs are still valid in the latest releases/pre-releases.