Bukkit Error: Exception ticking world entities

Hello

I'm having a lot of errors of this type, and servers down:

Code:

2013-01-24 09:46:24 [SEVERE] net.minecraft.server.v1_4_R1.ReportedException: Exception ticking world entities
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.MinecraftServer.r(MinecraftServer.java:584)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.DedicatedServer.r(DedicatedServer.java:224)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.MinecraftServer.q(MinecraftServer.java:494)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.MinecraftServer.run(MinecraftServer.java:427)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.ThreadServerApplication.run(SourceFile:849)
2013-01-24 09:46:24 [SEVERE] Caused by: java.lang.NullPointerException
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.World.tickEntities(World.java:1231)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.WorldServer.tickEntities(WorldServer.java:445)
2013-01-24 09:46:24 [SEVERE]    at net.minecraft.server.v1_4_R1.MinecraftServer.r(MinecraftServer.java:580)
2013-01-24 09:46:24 [SEVERE]    ... 4 more
2013-01-24 09:46:24 [SEVERE] Encountered an unexpected exception ReportedException
net.minecraft.server.v1_4_R1.ReportedException: Exception ticking world entities
    at net.minecraft.server.v1_4_R1.MinecraftServer.r(MinecraftServer.java:584)
    at net.minecraft.server.v1_4_R1.DedicatedServer.r(DedicatedServer.java:224)
    at net.minecraft.server.v1_4_R1.MinecraftServer.q(MinecraftServer.java:494)
    at net.minecraft.server.v1_4_R1.MinecraftServer.run(MinecraftServer.java:427)
    at net.minecraft.server.v1_4_R1.ThreadServerApplication.run(SourceFile:849)
Caused by: java.lang.NullPointerException
    at net.minecraft.server.v1_4_R1.World.tickEntities(World.java:1231)
    at net.minecraft.server.v1_4_R1.WorldServer.tickEntities(WorldServer.java:445)
    at net.minecraft.server.v1_4_R1.MinecraftServer.r(MinecraftServer.java:580)
    ... 4 more
2013-01-24 09:46:24 [SEVERE] This crash report has been saved to: /./crash-reports/crash-2013-01-24_09.46.24-server.txt

And this is the crash report: http://pastebin.com/v5KhfCzv

Maybe the world called "Borjan" I have this corrupt?

 

No support for offline servers