Problem my server keeps crashing

[polesy]

my server keeps crashing all i'll got

---- Minecraft Crash Report ----
// Hi. I'm Minecraft, and I'm a crashaholic.

Time: 3/1/13 11:11 PM
Description: Exception ticking world

java.lang.NullPointerException
at im.b(ChunkProviderServer.java:327)
at in.b(WorldServer.java:166)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:669)
at ho.r(DedicatedServer.java:269)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)
at fy.run(SourceFile:849)


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- Head --
Stacktrace:
at im.b(ChunkProviderServer.java:327)
at in.b(WorldServer.java:166)

-- Affected level --
Details:
Level name: world
All players: 0 total; []
Chunk stats: ServerChunkCache: 5 Drop: 1
Level seed: 568688860
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (0,0,0), Chunk: (at 0,0,0 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 0 game time, 0 day time
Level dimension: 0
Level storage version: 0x00000 - Unknown?
Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)
Level game mode: Game mode: survival (ID 0). Hardcore: false. Cheats: false
Stacktrace:
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:669)
at ho.r(DedicatedServer.java:269)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:599)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497)
at fy.run(SourceFile:849)

-- System Details --
Details:
Minecraft Version: 1.4.7
Operating System: Linux (amd64) version 2.6.32-042stab072.10
Java Version: 1.7.0_10, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 886759160 bytes (845 MB) / 1140850688 bytes (1088 MB) up to 1602224128 bytes (1528 MB)
JVM Flags: 25 total; -XX:+UseG1GC -XX:ThreadPriorityPolicy=42 -XX:CompileThreshold=1500 -XX:+TieredCompilation -XXarallelGCThreads=1 -XX:TargetSurvivorRatio=90 -XX:MaxTenuringThreshold=15 -XX:+UnlockExperimentalVMOptions -XX:+UseAdaptiveGCBoundary -XXermSize=64M -XX:MaxPermSize=256M -XX:+UseGCOverheadLimit -XX:+UseBiasedLocking -Xnoclassgc -Xverify:none -XX:UseSSE=3 -XX:+UseThreadPriorities -XX:+UseLargePages -XX:+UseStringCache -XX:+OptimizeStringConcat -XX:+UseFastAccessorMethods -Xrs -XX:+UseCompressedOops -XX:+AggressiveOpts -Xmx1527M
AABB Pool Size: 1962 (109872 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Suspicious classes: FML and Forge are installed
IntCache: cache: 0, tcache: 0, allocated: 1, tallocated: 63
FML: MCP v7.26a FML v4.7.32.553 Minecraft Forge 6.6.1.524 60 mods loaded, 60 mods active