i got this error when using the new snapshot 12w34b:
[SEVERE] Encountered an unexpected exception ArrayIndexOutOfBoundsException
java.lang.ArrayIndexOutOfBoundsException: 5
at ok.bA(SourceFile:245)
at vt.a(SourceFile:162)
at vt.a(SourceFile:139)
at gv.b(SourceFile:113)
at net.minecraft.server.MinecraftServer.r(SourceFile:432)
at fx.r(SourceFile:222)
at net.minecraft.server.MinecraftServer.q(SourceFile:380)
at net.minecraft.server.MinecraftServer.run(SourceFile:313)
at es.run(SourceFile:536)
2012-08-25 21:29:12 [SEVERE] This crash report has been saved to: C:\Users\Acer\Documents\MINECRAFT\Server\.\crash-reports\crash-2012-08-25_21.29.12-server.txt
2012-08-25 21:30:24 [INFO] Starting minecraft server version 12w34b
2012-08-25 21:30:24 [INFO] Loading properties
2012-08-25 21:30:24 [INFO] Default game type: SURVIVAL
2012-08-25 21:30:24 [INFO] Generating keypair
2012-08-25 21:30:25 [INFO] Starting Minecraft server on 5.71.2.52:25565
2012-08-25 21:30:25 [WARNING] **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
2012-08-25 21:30:25 [WARNING] The server will make no attempt to authenticate usernames. Beware.
2012-08-25 21:30:25 [WARNING] While this makes the game possible to play without internet access, it also opens up the ability for hackers to connect with any username they choose.
2012-08-25 21:30:25 [WARNING] To change this, set "online-mode" to "true" in the server.properties file.
2012-08-25 21:30:25 [INFO] Preparing level "world"
2012-08-25 21:30:25 [INFO] Preparing start region for level 0
2012-08-25 21:30:26 [INFO] Done (1.084s)! For help, type "help" or "?"
2012-08-25 21:31:42 [INFO] Le_Wild[/5.71.2.52:50542] logged in with entity id 62 at (151.5, 78.62000000476837, 64.5)
2012-08-25 21:31:42 [SEVERE] Encountered an unexpected exception ArrayIndexOutOfBoundsException
java.lang.ArrayIndexOutOfBoundsException: 5
at ok.bA(SourceFile:245)
at vt.a(SourceFile:162)
at vt.a(SourceFile:139)
at gv.b(SourceFile:113)
at net.minecraft.server.MinecraftServer.r(SourceFile:432)
at fx.r(SourceFile:222)
at net.minecraft.server.MinecraftServer.q(SourceFile:380)
at net.minecraft.server.MinecraftServer.run(SourceFile:313)
at es.run(SourceFile:536)
2012-08-25 21:31:42 [SEVERE] This crash report has been saved to: C:\Users\Acer\Documents\MINECRAFT\Server\.\crash-reports\crash-2012-08-25_21.31.42-server.txt
[SEVERE] Encountered an unexpected exception ArrayIndexOutOfBoundsException
java.lang.ArrayIndexOutOfBoundsException: 5
at ok.bA(SourceFile:245)
at vt.a(SourceFile:162)
at vt.a(SourceFile:139)
at gv.b(SourceFile:113)
at net.minecraft.server.MinecraftServer.r(SourceFile:432)
at fx.r(SourceFile:222)
at net.minecraft.server.MinecraftServer.q(SourceFile:380)
at net.minecraft.server.MinecraftServer.run(SourceFile:313)
at es.run(SourceFile:536)
2012-08-25 21:29:12 [SEVERE] This crash report has been saved to: C:\Users\Acer\Documents\MINECRAFT\Server\.\crash-reports\crash-2012-08-25_21.29.12-server.txt
2012-08-25 21:30:24 [INFO] Starting minecraft server version 12w34b
2012-08-25 21:30:24 [INFO] Loading properties
2012-08-25 21:30:24 [INFO] Default game type: SURVIVAL
2012-08-25 21:30:24 [INFO] Generating keypair
2012-08-25 21:30:25 [INFO] Starting Minecraft server on 5.71.2.52:25565
2012-08-25 21:30:25 [WARNING] **** SERVER IS RUNNING IN OFFLINE/INSECURE MODE!
2012-08-25 21:30:25 [WARNING] The server will make no attempt to authenticate usernames. Beware.
2012-08-25 21:30:25 [WARNING] While this makes the game possible to play without internet access, it also opens up the ability for hackers to connect with any username they choose.
2012-08-25 21:30:25 [WARNING] To change this, set "online-mode" to "true" in the server.properties file.
2012-08-25 21:30:25 [INFO] Preparing level "world"
2012-08-25 21:30:25 [INFO] Preparing start region for level 0
2012-08-25 21:30:26 [INFO] Done (1.084s)! For help, type "help" or "?"
2012-08-25 21:31:42 [INFO] Le_Wild[/5.71.2.52:50542] logged in with entity id 62 at (151.5, 78.62000000476837, 64.5)
2012-08-25 21:31:42 [SEVERE] Encountered an unexpected exception ArrayIndexOutOfBoundsException
java.lang.ArrayIndexOutOfBoundsException: 5
at ok.bA(SourceFile:245)
at vt.a(SourceFile:162)
at vt.a(SourceFile:139)
at gv.b(SourceFile:113)
at net.minecraft.server.MinecraftServer.r(SourceFile:432)
at fx.r(SourceFile:222)
at net.minecraft.server.MinecraftServer.q(SourceFile:380)
at net.minecraft.server.MinecraftServer.run(SourceFile:313)
at es.run(SourceFile:536)
2012-08-25 21:31:42 [SEVERE] This crash report has been saved to: C:\Users\Acer\Documents\MINECRAFT\Server\.\crash-reports\crash-2012-08-25_21.31.42-server.txt
I am using the snapshot as well and yes its generated by the snapshot server.