I am getting an error when i try to do any command in voxelsniper. My server is currently running on 1.5.2. Please help!!!!

Oh Yeah... That's like telling a developer: Hey your software doesn't work. Help!!!

No but seriously, how are we supposed to help without knowing which version of sniper you're running? Does the console show any stack trace? Which java version do you use.

22:59:31 [SEVERE] Error occurred while enabling VoxelSniper v5.168.5-SNAPSHOT-jnks195 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_4_R1/EntityLiving
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Class.java:2398)
at java.lang.Class.getConstructor0(Class.java:2708)
at java.lang.Class.getConstructor(Class.java:1659)
at com.thevoxelbox.voxelsniper.SniperBrushes.getBrush(SniperBrushes.java:240)
at com.thevoxelbox.voxelsniper.SniperBrushes.getSniperBrushes(SniperBrushes.java:180)
at com.thevoxelbox.voxelsniper.MetricsManager.start(MetricsManager.java:138)
at com.thevoxelbox.voxelsniper.VoxelSniper.onEnable(VoxelSniper.java:314)
at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:457)
at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:381)
at org.bukkit.craftbukkit.v1_5_R3.CraftServer.loadPlugin(CraftServer.java:282)
at org.bukkit.craftbukkit.v1_5_R3.CraftServer.enablePlugins(CraftServer.java:264)
at org.bukkit.craftbukkit.v1_5_R3.CraftServer.reload(CraftServer.java:605)
at org.bukkit.Bukkit.reload(Bukkit.java:185)
at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:23)
at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:189)
at org.bukkit.craftbukkit.v1_5_R3.CraftServer.dispatchCommand(CraftServer.java:523)
at org.bukkit.craftbukkit.v1_5_R3.CraftServer.dispatchServerCommand(CraftServer.java:512)
at net.minecraft.server.v1_5_R3.DedicatedServer.an(DedicatedServer.java:262)
at net.minecraft.server.v1_5_R3.DedicatedServer.r(DedicatedServer.java:227)
at net.minecraft.server.v1_5_R3.MinecraftServer.q(MinecraftServer.java:477)
at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:410)
at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_4_R1.EntityLiving
at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:70)
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
... 24 more

You're using the wrong combination of Bukkit/Sniper . Grab the latest build
from http://ci.thevoxelbox.com