Miért csinálja ezt a coolcraft?

amikor elindítom az 1 játékos-t a világba belépek akkor ezt írja ki: Minecraft has crashed!

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Minecraft has stopped running because it encountered a problem; Sending packet

A full error report has been saved to C:\Documents and Settings\Szgál Mariann\Application Data\.coolcraft.hu\crash-reports\crash-2013-09-10_16.21.12-server.txt - Please include a copy of that file (Not this screen!) if you report this crash to anyone; without it, they will not be able to help fix the crash :(

--- BEGIN ERROR REPORT 2411db3f --------

Full report at:

C:\Documents and Settings\Szgál Mariann\Application Data\.coolcraft.hu\crash-reports\crash-2013-09-10_16.21.12-server.txt

Please show that file to Mojang, NOT just this screen!

Generated 2013.09.10. 16:21

-- Head --

Stacktrace:

at ch.b(SourceFile:107)

at ch.a(SourceFile:39)

-- Packet being sent --

Details:

Packet ID: 4

Packet class: fh

Stacktrace:

at jh.b(SourceFile:430)

at gu.b(SourceFile:669)

at gu.a(SourceFile:79)

at bjj.b(SourceFile:73)

at net.minecraft.server.MinecraftServer.r(SourceFile:480)

at net.minecraft.server.MinecraftServer.q(SourceFile:397)

at bjg.q(IntegratedServer.java:171)

at net.minecraft.server.MinecraftServer.run(SourceFile:331)

at gp.run(SourceFile:573)

-- System Details --

Details:

Minecraft Version: 1.5.2

Operating System: Windows XP (x86) version 5.1

Java Version: 1.7.0_25, Oracle Corporation

Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation

Memory: 106822192 bytes (101 MB) / 259522560 bytes (247 MB) up to 259522560 bytes (247 MB)

JVM Flags: 0 total;

AABB Pool Size: 440 (24640 bytes; 0 MB) allocated, 440 (24640 bytes; 0 MB) used

Suspicious classes: BlockSarga, BlockNarancs, BlockDikk, ...]

IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0

Profiler Position: N/A (disabled)

Vec3 Pool Size: 63 (3528 bytes; 0 MB) allocated, 63 (3528 bytes; 0 MB) used

Player Count: 0 / 8; []

Type: Integrated Server (map_client.txt)

Is Modded: Very likely; Jar signature invalidated

java.lang.NullPointerException

at ch.b(SourceFile:107)

at ch.a(SourceFile:39)

at jh.b(SourceFile:430)

at gu.b(SourceFile:669)

at gu.a(SourceFile:79)

at bjj.b(SourceFile:73)

at net.minecraft.server.MinecraftServer.r(SourceFile:480)

at net.minecraft.server.MinecraftServer.q(SourceFile:397)

at bjg.q(IntegratedServer.java:171)

at net.minecraft.server.MinecraftServer.run(SourceFile:331)

at gp.run(SourceFile:573)

--- END ERROR REPORT a3e43b42 ----------

mit tegyek?