Bukkit or me (Crashing on PlayerQuitEvent)

Well i think the Name covers what is happening (Server Crashing On PlayerQuitEvent)

Error: (not to big so not a pastebin link)

Code:java

10.09 09:51:21 [Server] ERROR This crash report has been saved to: /./crash-reports/crash-2014-09-10_09.51.21-server.txt
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:469) [craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.MinecraftServer.u(MinecraftServer.java:589) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.MojangStatisticsGenerator.b(SourceFile:97) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.DedicatedServer.a(DedicatedServer.java:273) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.MinecraftServer.a(MinecraftServer.java:1108) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.PlayerList.getSeenPlayers(PlayerList.java:1106) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO at net.minecraft.server.v1_7_R4.WorldNBTStorage.getSeenPlayers(WorldNBTStorage.java:246) ~[craftbukkit-devBuild3108.jar:git-Bukkit-1.7.9-R0.2-20-g0b2ed13-b3108jnks]
10.09 09:51:21 [Server] INFO java.lang.NullPointerException
10.09 09:51:21 [Server] ERROR Encountered an unexpected exception
10.09 09:51:21 [Server] WARN Failed to save player data for candyfloss20