Что делать помогите!!! Играю на серваке в майнкрафте 1.4.7

4.7 обновили до 1.5
Я скачиваю их клиент включаю майнкрафт
и мне ошибка:
Minecraft has crashed
----------------------

Minecraft has stopped running because it encountered a problem; Failed to start game

A full error report has been saved to C:\Users\Fedor\AppData\Roaming\.minecraft\crash-reports\crash-2013-03-28_22.40.31-client.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 a4126b59 --------
Full report at:
C:\Users\Fedor\AppData\Roaming\.minecraft\crash-reports\crash-2013-03-28_22.40.31-client.txt
Please show that file to Mojang, NOT just this screen!

Generated 28.03.13 22:40

-- System Details --
Details:
Minecraft Version: 1.5.1
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.7.0_17, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 432623448 bytes (412 MB) / 518979584 bytes (494 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
LWJGL: 2.4.2
OpenGL: N11M-GE2/PCI/SSE2 GL version 3.1 NVIDIA 189.92, NVIDIA Corporation
Is Modded: Very likely; Jar signature invalidated
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~~ERROR~~ NullPointerException: null

java.lang.NullPointerException
at java.io.Reader.(Unknown Source)
at java.io.InputStreamReader.(Unknown Source)
at bp.a(SourceFile:64)
at bp.a(SourceFile:100)
at net.minecraft.client.Minecraft.a(SourceFile:252)
at avv.a(SourceFile:56)
at net.minecraft.client.Minecraft.run(SourceFile:507)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT 957204f6 ----------

Помогите плизз!