This is a really weird issue which has started happening recently.
I use Citizens2 and have NPC "player statues" on my server for players who have reached a particular rank. The NPC's don't do anything, they just stand on a pedestal and are for display only. The NPC's are created by "/npc create --type player" so they have the same name as the actual player and download their skin.

I recently relocated all the NPC's to a location away from my default spawn (it was filling up) and used MultiVerse Portals to create a two-way portal from my spawn area to the new NPC "Player Hall of Fame".

Since then, the following behaviour has been experienced by a number of players.

• Player A is minding their own business somewhere in the world
• Player B walks through the portal to the Citizens NPC "Player Hall of Fame".
• Player A is teleported to the Citizens NPC "Player Hall of Fame", specifically to the exact same x y z coordinates as their named NPC statue.

Any idea why this is happening and how I can prevent it? Thanks.

2013-09-07 09:00:14 [INFO] This server is running CraftBukkit version git-Spigot-1091 (MC: 1.6.2) (Implementing API version 1.6.2-R0.2-SNAPSHOT)
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2013-09-07 09:00:18 [INFO] [Multiverse-NetherPortals] Loading Multiverse-NetherPortals v2.4-b530
2013-09-07 09:00:18 [INFO] [Enjin Minecraft Plugin] Loading Enjin Minecraft Plugin v2.4.9-bukkit
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Very strange. But this sounds more like a bug in Citizens than in MV because I have no idea why MV would teleport player A in that case.