Constant server crashes

[Seanbeag]

Title: Constant server crashes

Version: 3.1.2

OS: win 7

Java Version: latest

Description of Problem:

Server crashes regularly. Sometimes it gives this error

Error Messages:

Error Log:

01.12 19:09:53 [server] INFO at net.minecraft.server.ThreadServerApplication.run(SourceFile:492)

01.12 19:09:53 [server] INFO at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:467)

01.12 19:09:53 [server] INFO at net.minecraft.server.MinecraftServer.w(MinecraftServer.java:579)

01.12 19:09:53 [server] INFO at net.minecraft.server.NetworkListenThread.a(NetworkListenThread.java:66)

01.12 19:09:53 [server] INFO at net.minecraft.server.NetLoginHandler.a(NetLoginHandler.java:50)

01.12 19:09:53 [server] INFO at net.minecraft.server.NetLoginHandler.b(NetLoginHandler.java:111)

01.12 19:09:53 [server] INFO at net.minecraft.server.ServerConfigurationManager.attemptLogin(ServerConfigurationManager.java:213)

01.12 19:09:53 [server] INFO java.lang.NullPointerException

01.12 19:09:53 [server] WARNING Failed to handle packet: java.lang.NullPointerException

01.12 19:09:53 [server] INFO Disconnecting aaron1708 [/83.70.217.203:60069]: Internal server error

[rsitges]

All of mc has crashed