Buffer Overflow?

After a while away from my computer...
GoldScape was on...

And when I came back I saw this...

Code:

Fatal: Buffer overflow.
ClientHandler: Client kyle v2 disconnected.
[client-1-kyle v2]: Error
Exception in thread "main" java.lang.NullPointerException
        at client.sendQuest(client.java:9024)
        at client.setSkillLevel(client.java:10151)
        at client.process(client.java:16179)
        at PlayerHandler.process(PlayerHandler.java:137)
        at server.main(server.java:50)

And no one could connect...


Can anyone tell me how I fix this?

Thanks
-Syth4