Can't run Minecraft Multiplayer 1.8

My Java is updated, but I still have problems with 1.8...

Minecraft Crash Report ----
// I just don't know what went wrong 😞

Time: 11.10.14 10:52
Description: Rendering screen

java.lang.IllegalArgumentException: bad Base64 input character at 5191: 0 (decimal)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:247)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:197)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:188)
at bzs.c(SourceFile:212)
at bzs.a(SourceFile:145)
at buu.a(SourceFile:25)
at bvk.b(SourceFile:409)
at bvk.a(SourceFile:217)
at bzp.a(SourceFile:291)
at cji.b(SourceFile:1020)
at bsu.as(SourceFile:903)
at bsu.a(SourceFile:314)
at net.minecraft.client.main.Main.main(SourceFile:120)

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

– Head –
Stacktrace:
at io.netty.handler.codec.base64.Base64.decode(Base64.java:247)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:197)
at io.netty.handler.codec.base64.Base64.decode(Base64.java:188)
at bzs.c(SourceFile:212)
at bzs.a(SourceFile:145)
at buu.a(SourceFile:25)
at bvk.b(SourceFile:409)
at bvk.a(SourceFile:217)
at bzp.a(SourceFile:291)

– Screen render details –
Details:
Screen name: bzp
Mouse location: Scaled: (232, 146). Absolute: (464, 186)
Screen size: Scaled: (427, 240). Absolute: (854, 480). Scale factor of 2
Stacktrace:
at cji.b(SourceFile:1020)
at bsu.as(SourceFile:903)
at bsu.a(SourceFile:314)
at net.minecraft.client.main.Main.main(SourceFile:120)

– System Details –
Details:
Minecraft Version: 1.8
Operating System: Windows XP (x86) version 5.1
Java Version: 1.7.0_67, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 70833208 bytes (67 MB) / 155774976 bytes (148 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1024M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.8
LWJGL: 2.9.1
OpenGL: ATI Radeon HD 5500 Series GL version 2.1.9115, ATI Technologies Inc.
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because ARB_framebuffer_object is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.

Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (UK)
Profiler Position: N/A (disabled)