problém s javou

Dobrý den, mám tento problém asi nejspíš s javou, dřív šel minecraft normálně, ale včera jsem ho spustil a najednou sem logo Mojang narolovalo pomalu a ukazovalo to 1 fps a pak ukazalo tohle

Minecraft has crashed!
----------------------
--- BEGIN ERROR REPORT d62dd892 --------
Generated 28.9.12 7:59

- Minecraft Version: 1.3.2
- Operating System: Windows XP (x86) version 5.1
- Java Version: 1.7.0_07, Oracle Corporation
- Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
- Memory: 453640800 bytes (432 MB) / 518979584 bytes (494 MB) up to 1037959168 bytes (989 MB)
- JVM Flags: 2 total; -Xms512m -Xmx1024m
- LWJGL: 2.4.2
- OpenGL: GeForce 6200/PCI/SSE2 GL version 2.1.2, NVIDIA Corporation
- Is Modded: Probably not
- Type: Client
- Texture Pack: Default
- Profiler Position: N/A (disabled)

java.lang.NullPointerException
at java.io.Reader.<init>(Unknown Source)
at java.io.InputStreamReader.<init>(Unknown Source)
at ak.a(SourceFile:56)
at ak.a(SourceFile:91)
at net.minecraft.client.Minecraft.a(SourceFile:250)
at net.minecraft.client.Minecraft.run(SourceFile:516)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT 3d68b08 ----------

co stím ? předem děkuji za odpověď