My Minecraft is crashing y

this is the crash report

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

Minecraft has stopped running because it encountered a problem; Unexpected error
This error has been saved to C:\Users\Ben\AppData\Roaming\.minecraft\crash-reports\crash-2012-11-04_11.44.00-client.txt for your convenience. Please include a copy of this file if you report this crash to anyone.



--- BEGIN ERROR REPORT 5714be3c --------
Generated 04/11/12 11:44

- Minecraft Version: 1.4.2
- 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: 432220408 bytes (412 MB) / 514523136 bytes (490 MB) up to 954466304 bytes (910 MB)
- JVM Flags: 2 total; -Xms512m -Xmx1024m
- AABB Pool Size: 403 (22568 bytes; 0 MB) allocated, 403 (22568 bytes; 0 MB) used
- LWJGL: 2.4.2
- OpenGL: Intel(R) HD Graphics Family GL version 3.0.0 - Build 8.15.10.2342, Intel
- Is Modded: Very likely
- Type: Client
- Texture Pack: Default
- Profiler Position: N/A (disabled)
- Vec3 Pool Size: 45 (2520 bytes; 0 MB) allocated, 45 (2520 bytes; 0 MB) used
- World MpServer Entities: 4 total; [axc['bendy432'/301, l='MpServer', x=-11.50, y=71.24, z=165.50], qa['Zombie'/76, l='MpServer', x=-19.50, y=43.00, z=188.50], oo['Sheep'/77, l='MpServer', x=-21.97, y=63.00, z=176.50], oo['Sheep'/78, l='MpServer', x=-20.56, y=63.00, z=177.25]]
- World MpServer Players: 1 total; [axc['bendy432'/301, l='MpServer', x=-11.50, y=71.24, z=165.50]]
- World MpServer Chunk Stats: MultiplayerChunkCache: 10
- Forced Entities: 4 total; [qa['Zombie'/76, l='MpServer', x=-19.50, y=43.00, z=188.50], oo['Sheep'/77, l='MpServer', x=-21.97, y=63.00, z=176.50], oo['Sheep'/78, l='MpServer', x=-20.56, y=63.00, z=177.25], axc['bendy432'/301, l='MpServer', x=-11.50, y=71.24, z=165.50]]
- Retry Entities: 0 total; []

java.lang.NoClassDefFoundError: com/pclewis/mcpatcher/mod/RenderPassAPI
	at ayt.a(SourceFile:813)
	at ayt.b(SourceFile:732)
	at net.minecraft.client.Minecraft.J(SourceFile:604)
	at net.minecraft.client.Minecraft.run(SourceFile:534)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: com.pclewis.mcpatcher.mod.RenderPassAPI
	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)
	... 5 more
--- END ERROR REPORT 3f54df9d ----------

plz help 🙂 🙂 🙂