I don't know anything

---- Minecraft Crash Report ----
// Oops.

Time: 14/06/2013 9:01
Description: Rendering entity in world

java.lang.NoClassDefFoundError: cpw/mods/fml/common/IWorldGenerator
	at bgf.a(RenderBlocks.java:7611)
	at bhi.a(SourceFile:81)
	at bhi.a(SourceFile:22)
	at bgy.a(SourceFile:201)
	at bgy.a(SourceFile:181)
	at bfy.a(SourceFile:307)
	at bfq.a(SourceFile:894)
	at bfq.b(SourceFile:745)
	at net.minecraft.client.Minecraft.K(SourceFile:597)
	at net.minecraft.client.Minecraft.run(SourceFile:526)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: cpw.mods.fml.common.IWorldGenerator
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 11 more


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

-- Head --
Stacktrace:
	at bgf.a(RenderBlocks.java:7611)
	at bhi.a(SourceFile:81)
	at bhi.a(SourceFile:22)

-- Entity being rendered --
Details:
	Entity Type: Item (rh)
	Entity ID: 167
	Entity Name: item.tile.dirt
	Entity's Exact location: 146.13, 68.13, 246.88
	Entity's Block location: World: (146,68,246), Chunk: (at 2,4,6 in 9,15; contains blocks 144,0,240 to 159,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Entity's Momentum: 0.00, -0.00, 0.00

-- Renderer details --
Details:
	Assigned renderer: bhi@a20a63
	Location: -0.38,-1.50,0.38 - World: (-1,-2,0), Chunk: (at 15,-1,0 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)
	Rotation: 352.96875
	Delta: 0.01636076
Stacktrace:
	at bgy.a(SourceFile:201)
	at bgy.a(SourceFile:181)
	at bfy.a(SourceFile:307)
	at bfq.a(SourceFile:894)

-- Affected level --
Details:
	Level name: MpServer
	All players: 1 total; [bdv['MeGusta'/358, l='MpServer', x=146.50, y=69.62, z=246.50]]
	Chunk stats: MultiplayerChunkCache: 25
	Level seed: 0
	Level generator: ID 00 - default, ver 1. Features enabled: false
	Level generator options: 
	Level spawn location: World: (152,64,252), Chunk: (at 8,4,12 in 9,15; contains blocks 144,0,240 to 159,255,255), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
	Level time: 89 game time, 89 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: 18 total; [sj['Zombie'/205, l='MpServer', x=178.50, y=48.00, z=211.50], sh['Spider'/204, l='MpServer', x=190.78, y=33.00, z=223.41], sf['Skeleton'/207, l='MpServer', x=188.50, y=32.00, z=232.50], qg['Bat'/168, l='MpServer', x=158.13, y=42.00, z=287.06], sf['Skeleton'/206, l='MpServer', x=190.50, y=32.00, z=232.50], bdv['MeGusta'/358, l='MpServer', x=146.50, y=69.62, z=246.50], rh['item.tile.dirt'/167, l='MpServer', x=146.13, y=68.13, z=246.88], rg['Falling Block'/429, l='MpServer', x=156.50, y=6.03, z=255.50], rg['Falling Block'/428, l='MpServer', x=156.50, y=6.49, z=254.50], sj['Zombie'/178, l='MpServer', x=174.50, y=48.00, z=212.50], qo['Sheep'/212, l='MpServer', x=178.19, y=66.00, z=241.34], qg['Bat'/213, l='MpServer', x=177.00, y=50.00, z=268.39], qg['Bat'/179, l='MpServer', x=161.25, y=44.68, z=278.69], sf['Skeleton'/214, l='MpServer', x=185.50, y=46.00, z=275.50], qo['Sheep'/208, l='MpServer', x=178.50, y=66.00, z=238.50], sf['Skeleton'/209, l='MpServer', x=187.50, y=32.00, z=240.50], qo['Sheep'/210, l='MpServer', x=180.09, y=66.00, z=241.22], qo['Sheep'/211, l='MpServer', x=178.19, y=66.00, z=242.97]]
	Retry entities: 0 total; []
Stacktrace:
	at bds.a(SourceFile:282)
	at net.minecraft.client.Minecraft.b(SourceFile:1881)
	at net.minecraft.client.Minecraft.run(SourceFile:535)
	at java.lang.Thread.run(Unknown Source)

-- System Details --
Details:
	Minecraft Version: 1.5.2
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_21, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
	Memory: 122905544 bytes (117 MB) / 235962368 bytes (225 MB) up to 1037959168 bytes (989 MB)
	JVM Flags: 1 total; -Xmx1024m
	AABB Pool Size: 6694 (374864 bytes; 0 MB) allocated, 490 (27440 bytes; 0 MB) used
	Suspicious classes: [CrazyOres.common.core.mod_CrazyOres, COTab]
	IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 63
	LWJGL: 2.4.2
	OpenGL: Intel(R) HD Graphics GL version 4.0.0 - Build 9.17.10.2932, Intel
	Is Modded: Very likely; Jar signature invalidated
	Type: Client (map_client.txt)
	Texture Pack: Default
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: 452 (25312 bytes; 0 MB) allocated, 116 (6496 bytes; 0 MB) used