Hey guys! 
  
I hope you can help me  minecraft crashes every 1-5 Minutes 
  
I got these mods: 
Forge 6.0.1.355 
optifine 1.4.2 hd_B2 
GuiApi 0.14.8 1.4.2 
zanmap 142f 
mos Creatures 
custom mob spawner 1.7.1 
  
installed in this order 
  
Here is the log: 
  
---- Minecraft Crash Report ---- 
// Oops. 
  
Time: 13.11.12 19:12 
Description: Exception in server tick loop 
  
java.util.ConcurrentModificationException 
	at java.util.ArrayList$Itr.checkForComodification(Unknown Source) 
	at java.util.ArrayList$Itr.next(Unknown Source) 
	at ib.b(PlayerManager.java:71) 
	at ie.b(WorldServer.java:136) 
	at net.minecraft.server.MinecraftServer.r(MinecraftServer.java:653) 
	at net.minecraft.server.MinecraftServer.q(MinecraftServer.java:590) 
	at bcb.q(IntegratedServer.java:110) 
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:497) 
	at fp.run(SourceFile:818) 
  
Relevant Details: 
- Minecraft Version: 1.4.2 
- Operating System: Windows 7 (amd64) version 6.1 
- Java Version: 1.7.0_09, Oracle Corporation 
- Java VM Version: Java HotSpot 64-Bit Server VM (mixed mode), Oracle Corporation 
- Memory: 150369688 bytes (143 MB) / 592248832 bytes (564 MB) up to 954466304 bytes (910 MB) 
- JVM Flags: 2 total; -Xms512m -Xmx1024m 
- AABB Pool Size: 8562 (479472 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used 
- FML: MCP v7.19 FML v4.2.18.433 Minecraft Forge 6.0.1.355 Optifine OptiFine_1.4.2_HD_B2 4 mods loaded, 4 mods active 
	mcp [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available 
	FML [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available 
	Forge [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available 
	MoCreatures [DrZhark's Mo'Creatures Mod] (DrZharks MoCreatures Mod v4.1.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available 
- Is Modded: Definitely; 'forge,fml' 
- Profiler Position: N/A (disabled) 
- Vec3 Pool Size: 2286 (128016 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used 
- Player Count: 1 / 8; [ih['tostes'/5, l='Graf', x=227,78, y=63,00, z=781,25]] 
- World Graf Entities: 0 total; [] 
- World Graf Players: 0 total; [] 
- World Graf Chunk Stats: ServerChunkCache: 0 Drop: 0 
- Type: Integrated Server 
  
Can you help me? Installed with new .jar for >6 times  
  
greetings!