Exception in server tick loop

---- Minecraft Crash Report ----
// Why did you do that?

Time: 2/22/13 3:46 PM
Description: Exception in server tick loop

java.lang.NullPointerException
at ic2.advancedmachines.common.TileEntityAdvancedMachine.operate(TileEntityAdvancedMachine.java:210)
at ic2.advancedmachines.common.TileEntityAdvancedMachine.g(TileEntityAdvancedMachine.java:96)
at xe.h(World.java:2020)
at ie.h(WorldServer.java:463)
at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:649)
at hg.r(DedicatedServer.java:241)
at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:585)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:492)
at fp.run(SourceFile:818)

Relevant Details:
- Minecraft Version: 1.4.2
- Operating System: Windows Server 2008 R2 (amd64) version 6.1
- Java Version: 1.7.0_05, Oracle Corporation
- Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
- Memory: 415404896 bytes (396 MB) / 590544896 bytes (563 MB) up to 1908932608 bytes (1820 MB)
- JVM Flags: 1 total; -Xmx2048M
- AABB Pool Size: 2062 (115472 bytes; 0 MB) allocated, 2027 (113512 bytes; 0 MB) used
- FML: ~ERROR~ NullPointerException: null
- Is Modded: Definitely; 'forge,fml'
- Profiler Position: N/A (disabled)
- Vec3 Pool Size: 319 (17864 bytes; 0 MB) allocated, 305 (17080 bytes; 0 MB) used
- Player Count: 0 / 16; []
- World FTB-Beta-A Entities: 14 total; [EntityBlock['unknown'/125, l='FTB-Beta-A', x=-81.50, y=35.45, z=-27.55], EntityBlock['unknown'/126, l='FTB-Beta-A', x=-81.55, y=35.50, z=-27.55], EntityBlock['unknown'/127, l='FTB-Beta-A', x=-81.50, y=39.45, z=-27.55], EntityBlock['unknown'/128, l='FTB-Beta-A', x=-71.55, y=35.50, z=-27.55], EntityBlock['unknown'/129, l='FTB-Beta-A', x=-81.50, y=35.45, z=-17.55], EntityBlock['unknown'/130, l='FTB-Beta-A', x=-81.55, y=35.50, z=-17.55], EntityBlock['unknown'/131, l='FTB-Beta-A', x=-71.55, y=35.50, z=-17.55], EntityBlock['unknown'/132, l='FTB-Beta-A', x=-81.50, y=39.45, z=-17.55], EntityBlock['unknown'/133, l='FTB-Beta-A', x=-81.55, y=35.45, z=-27.50], EntityBlock['unknown'/134, l='FTB-Beta-A', x=-71.55, y=35.45, z=-27.50], EntityBlock['unknown'/135, l='FTB-Beta-A', x=-81.55, y=39.45, z=-27.50], EntityBlock['unknown'/136, l='FTB-Beta-A', x=-71.55, y=39.45, z=-27.50], EntityTFSquirrel['Forest Squirrel'/404, l='FTB-Beta-A', x=-95.50, y=65.00, z=-35.50], EntityTFSquirrel['Forest Squirrel'/405, l='FTB-Beta-A', x=-94.50, y=66.00, z=-39.50]]
- World FTB-Beta-A Players: 0 total; []
- World FTB-Beta-A Chunk Stats: ServerChunkCache: 6 Drop: 0
- Type: Dedicated Server