I get this error when i enter like /addsniper PLxM

Or any command, doesn't seem to be working

Here is the errors in my console

[SEVERE] null
exception executing command 'b' in plugin VoxelSniper v5.168.5-SNAPSHOT-jnks198
java.lang.NoClassDefFoundError: net/minecraft/server/v1_4_R1/EntityLiving
java.lang.ClassNotFoundException: net.minecraft.server.v1_4_R1.EntityLiving

What bukkit version are you running?

I tip my hat for that issue title.

Craft Bukkit 1.5.1 Dev Release.
On Friday, April 5, 2013, Michael Braun wrote:

I tip my hat for that issue title. [image: ]

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Reply to this email directly or view it on GitHubhttps://github.com//issues/146#issuecomment-15936667
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You have to use the latest sniper build then as well. Grab it here:
http://ci.thevoxelbox.com