It keeps crashing when i want to type a word or something

Have the same problem:

Minecraft Crash Report ----
// Hey, that tickles! Hehehe!

Time: 10-07-2013 19:56
Description: Deserializing Message

java.lang.ClassCastException: com.google.gson.JsonPrimitive cannot be cast to com.google.gson.JsonObject
at cw.a(SourceFile:14)
at cw.deserialize(SourceFile:10)
at com.google.gson.TreeTypeAdapter.read(TreeTypeAdapter.java:58)
at com.google.gson.Gson.fromJson(Gson.java:795)
at com.google.gson.Gson.fromJson(Gson.java:761)
at com.google.gson.Gson.fromJson(Gson.java:710)
at com.google.gson.Gson.fromJson(Gson.java:682)
at cu.c(SourceFile:220)
at bct.a(SourceFile:522)
at dl.a(SourceFile:49)
at cn.b(SourceFile:354)
at bct.e(SourceFile:98)
at bda.b(SourceFile:60)
at ats.k(SourceFile:1386)
at ats.S(SourceFile:663)
at ats.d(SourceFile:619)
at net.minecraft.client.main.Main.main(SourceFile:101)

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

– Head –
Stacktrace:
at cw.a(SourceFile:14)
at cw.deserialize(SourceFile:10)
at com.google.gson.TreeTypeAdapter.read(TreeTypeAdapter.java:58)
at com.google.gson.Gson.fromJson(Gson.java:795)
at com.google.gson.Gson.fromJson(Gson.java:761)
at com.google.gson.Gson.fromJson(Gson.java:710)
at com.google.gson.Gson.fromJson(Gson.java:682)

– Serialized Message –
Details:
JSON string: Cannot send chat message.
Stacktrace:
at cu.c(SourceFile:220)
at bct.a(SourceFile:522)
at dl.a(SourceFile:49)
at cn.b(SourceFile:354)
at bct.e(SourceFile:98)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bdf['TugaKid'/234, l='MpServer', x=10,37, y=73,62, z=5,46]]
Chunk stats: MultiplayerChunkCache: 441
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (-10,82,10), Chunk: (at 6,5,10 in -1,0; contains blocks -16,0,0 to -1,255,15), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 10939565 game time, 11043865 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
Forced entities: 1 total; [bdf['TugaKid'/234, l='MpServer', x=10,37, y=73,62, z=5,46]]
Retry entities: 0 total; []
Server brand: craftbukkit
Server type: Non-integrated multiplayer server
Stacktrace:
at bda.a(SourceFile:284)
at ats.k(SourceFile:1393)
at ats.S(SourceFile:663)
at ats.d(SourceFile:619)
at net.minecraft.client.main.Main.main(SourceFile:101)

– Affected level –
Details:
Level name: MpServer
All players: 1 total; [bdf['TugaKid'/234, l='MpServer', x=10,37, y=73,62, z=5,46]]
Chunk stats: MultiplayerChunkCache: 441
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (-10,82,10), Chunk: (at 6,5,10 in -1,0; contains blocks -16,0,0 to -1,255,15), Region: (-1,0; contains chunks -32,0 to -1,31, blocks -512,0,0 to -1,255,511)
Level time: 10939565 game time, 11043865 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
Forced entities: 1 total; [bdf['TugaKid'/234, l='MpServer', x=10,37, y=73,62, z=5,46]]
Retry entities: 0 total; []
Server brand: craftbukkit
Server type: Non-integrated multiplayer server

– System Details –
Details:
Minecraft Version: 1.6.2
Operating System: Windows 8 (x86) version 6.2
Java Version: 1.7.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
Memory: 83136200 bytes (79 MB) / 146853888 bytes (140 MB) up to 518979584 bytes (494 MB)
JVM Flags: 1 total; -Xmx512M
AABB Pool Size: 16 (896 bytes; 0 MB) allocated, 14 (784 bytes; 0 MB) used
Suspicious classes: No suspicious classes found.
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.6.2
LWJGL: 2.9.0
OpenGL: ATI Radeon HD 4730 Series GL version 3.3.11653 Compatibility Profile Context, ATI Technologies Inc.
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Pack: Default
Current Language: Português (Portugal)
Profiler Position: N/A (disabled)
Vec3 Pool Size: 39 (2184 bytes; 0 MB) allocated, 13 (728 bytes; 0 MB) used

Duplicate of: [MC-20163] - Please use the search function to see if your bug has already been submitted.
Currently over 50% of tickets are being closed as duplicate.