My minecraft client keeps crashing on me?!?

I keep on crashing whenever i die or join a server and that never happened before any help?

This is my crash report




Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem; Unexpected error

A full error report has been saved to C:\Users\staples\AppData\Roaming\.minecraft\crash-reports\crash-2012-12-24_13.57.29-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 492061f8 --------
Full report at:
C:\Users\staples\AppData\Roaming\.minecraft\crash-reports\crash-2012-12-24_13.57.29-client.txt
Please show that file to Mojang, NOT just this screen!

Generated 12/24/12 1:57 PM

-- Head --
Stacktrace:
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at atk.<clinit>(GuiIngame.java:40)
at net.minecraft.client.Minecraft.a(SourceFile:441)

-- Affected level --
Details:
Level name: MpServer
All players: 3 total; [ays['WolfBondage'/148163, l='MpServer', x=1718.50, y=86.62, z=-1188.50], bah['warriorgirl97'/143852, l='MpServer', x=1718.63, y=85.00, z=-1183.75], bah['ollienorth19'/144456, l='MpServer', x=1718.84, y=92.00, z=-1204.75]]
Chunk stats: MultiplayerChunkCache: 120
Level seed: 0
Level generator: ID 00 - default, ver 1. Features enabled: false
Level generator options:
Level spawn location: World: (193,64,256), Chunk: (at 1,4,0 in 12,16; contains blocks 192,0,256 to 207,255,271), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)
Level time: 1117449 game time, 1200583 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: creative (ID 1). Hardcore: false. Cheats: false
Forced entities: 46 total; [ays['WolfBondage'/148163, l='MpServer', x=1718.50, y=86.62, z=-1188.50], ow['Bat'/145803, l='MpServer', x=1779.09, y=16.34, z=-1240.56], bah['warriorgirl97'/143852, l='MpServer', x=1718.63, y=85.00, z=-1183.75], bah['ollienorth19'/144456, l='MpServer', x=1718.83, y=92.00, z=-1201.25], qc['Creeper'/144939, l='MpServer', x=1692.31, y=45.00, z=-1111.66], bah['ollienorth19'/144456, l='MpServer', x=1718.84, y=92.00, z=-1204.75], qn['Skeleton'/146462, l='MpServer', x=1674.50, y=36.00, z=-1110.50], ow['Bat'/145804, l='MpServer', x=1780.42, y=11.55, z=-1233.58], qd['Enderman'/145278, l='MpServer', x=1703.50, y=18.00, z=-1149.00], ow['Bat'/145805, l='MpServer', x=1792.00, y=15.06, z=-1217.47], qn['Skeleton'/146463, l='MpServer', x=1676.50, y=36.00, z=-1110.50], qn['Skeleton'/142095, l='MpServer', x=1693.50, y=71.00, z=-1136.50], qr['Zombie'/142090, l='MpServer', x=1727.00, y=65.00, z=-1130.56], qr['Zombie'/145202, l='MpServer', x=1798.50, y=20.00, z=-1191.50], qc['Creeper'/142161, l='MpServer', x=1716.50, y=24.00, z=-1140.50], qr['Zombie'/142772, l='MpServer', x=1664.94, y=42.00, z=-1133.70], qd['Enderman'/147449, l='MpServer', x=1642.50, y=21.00, z=-1127.50], oy['Chicken'/139199, l='MpServer', x=1738.47, y=88.00, z=-1234.28], qn['Skeleton'/147448, l='MpServer', x=1654.25, y=13.22, z=-1119.69], oz['Cow'/139198, l='MpServer', x=1708.50, y=64.00, z=-1139.78], qn['Skeleton'/142643, l='MpServer', x=1745.84, y=44.00, z=-1144.72], pe['Sheep'/139197, l='MpServer', x=1773.94, y=76.00, z=-1190.53], pd['Pig'/139196, l='MpServer', x=1763.53, y=64.00, z=-1211.69], qn['Skeleton'/142642, l='MpServer', x=1751.50, y=44.00, z=-1145.50], oz['Cow'/139195, l='MpServer', x=1772.75, y=70.00, z=-1219.31], pe['Sheep'/139200, l='MpServer', x=1780.25, y=63.00, z=-1202.94], pe['Sheep'/139201, l='MpServer', x=1781.44, y=69.00, z=-1200.47], qd['Enderman'/144544, l='MpServer', x=1648.59, y=31.00, z=-1122.78], pe['Sheep'/139202, l='MpServer', x=1763.13, y=63.00, z=-1123.69], pd['Pig'/139203, l='MpServer', x=1682.34, y=81.00, z=-1135.91], px['item.item.dyePowder.black'/139205, l='MpServer', x=1655.88, y=42.13, z=-1137.84], oy['Chicken'/139206, l='MpServer', x=1706.63, y=76.00, z=-1109.88], ow['Bat'/141234, l='MpServer', x=1784.67, y=17.65, z=-1232.25], qn['Skeleton'/140975, l='MpServer', x=1774.31, y=32.00, z=-1243.34], qn['Skeleton'/146009, l='MpServer', x=1702.50, y=43.00, z=-1112.50], px['item.item.bone'/144897, l='MpServer', x=1694.16, y=71.13, z=-1138.06], qc['Creeper'/141461, l='MpServer', x=1765.50, y=44.00, z=-1145.50], bah['warriorgirl97'/143852, l='MpServer', x=1718.63, y=85.00, z=-1183.75], ow['Bat'/145776, l='MpServer', x=1672.00, y=21.10, z=-1152.56], ow['Bat'/145778, l='MpServer', x=1653.25, y=39.10, z=-1142.56], qr['Zombie'/142956, l='MpServer', x=1709.50, y=28.00, z=-1136.50], qr['Zombie'/144808, l='MpServer', x=1771.50, y=24.00, z=-1178.50], qr['Zombie'/144809, l='MpServer', x=1773.50, y=24.00, z=-1179.50], qc['Creeper'/145218, l='MpServer', x=1781.50, y=27.00, z=-1243.50], ow['Bat'/145842, l='MpServer', x=1733.24, y=28.00, z=-1113.34], bah['ollienorth19'/144456, l='MpServer', x=1718.84, y=92.00, z=-1204.75]]
Retry entities: 0 total; []
Stacktrace:
at ayp.a(SourceFile:281)
at net.minecraft.client.Minecraft.b(SourceFile:1871)
at net.minecraft.client.Minecraft.run(SourceFile:548)
at java.lang.Thread.run(Unknown Source)

-- System Details --
Details:
Minecraft Version: 1.4.6
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.7.0_07, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 413012448 bytes (393 MB) / 514523136 bytes (490 MB) up to 954466304 bytes (910 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
AABB Pool Size: 21834 (1222704 bytes; 1 MB) allocated, 591 (33096 bytes; 0 MB) used
Suspicious classes: [reifnsk.minimap.ReiMinimap, GuiScreenInterface, GuiOptionScreen]
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
LWJGL: 2.4.2
OpenGL: Intel(R) Graphics Media Accelerator HD GL version 2.1.0 - Build 8.15.10.1986, Intel
Is Modded: Very likely; Jar signature invalidated
Type: Client (map_client.txt)
Texture Pack: Default
Profiler Position: N/A (disabled)
Vec3 Pool Size: 1087 (60872 bytes; 0 MB) allocated, 125 (7000 bytes; 0 MB) used

java.lang.VerifyError: (class: reifnsk/minimap/ReiMinimap, method: onTickInGame signature: (FLnet/minecraft/client/Minecraft;)V) Bad type in putfield/putstatic
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at atk.<clinit>(GuiIngame.java:40)
at net.minecraft.client.Minecraft.a(SourceFile:441)
at net.minecraft.client.Minecraft.l(SourceFile:1072)
at net.minecraft.client.Minecraft.J(SourceFile:582)
at net.minecraft.client.Minecraft.run(SourceFile:534)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT a4939949 ----------