As you know, when a player falls from a certain hight, it generates particles. Unfortunatly on my server (http://timgaming.com/) we discovered that when a vanished player falls, those particles appear on the client, as per this picture:

http://i.imgur.com/nTlrhZm.png?1

Is still still present on the latest craftbukkit build?

It would appear that this issue does not exist with Beta Build | 1.7.2-R0.2