Server Error

Hi, I have a Minecraft Bukkit Server and an error keeps coming up on my Console. Do any of you know what is causing it? Thanks

at org.bukkit.plugin.RegisteredListener.callEvent(RegisteredListener.java:62)
at org.bukkit.plugin.SimplePluginManager.fireEvent(SimplePluginManager.java:477)
at org.bukkit.plugin.SimplePluginManager.callEvent(SimplePluginManager.java:462)
at net.minecraft.server.v1_5_R1.PlayerList.c(PlayerList.java:204)
at net.minecraft.server.v1_5_R1.PlayerList.a(PlayerList.java:100)
at net.minecraft.server.v1_5_R1.PendingConnection.d(PendingConnection.java:129)
at net.minecraft.server.v1_5_R1.PendingConnection.c(PendingConnection.java:44)
at net.minecraft.server.v1_5_R1.DedicatedServerConnectionThread.a(DedicatedServerConnectionThread.java:41)
at net.minecraft.server.v1_5_R1.DedicatedServerConnection.b(SourceFile:29)
at net.minecraft.server.v1_5_R1.MinecraftServer.r(MinecraftServer.java:580)
at net.minecraft.server.v1_5_R1.DedicatedServer.r(DedicatedServer.java:225)
at net.minecraft.server.v1_5_R1.MinecraftServer.q(MinecraftServer.java:476)
at net.minecraft.server.v1_5_R1.MinecraftServer.run(MinecraftServer.java:409)
at net.minecraft.server.v1_5_R1.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.NumberFormatException: For input string: "2.2"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:492)
at java.lang.Integer.valueOf(Integer.java:582)
at com.gmail.curlybraceproductions.bowwarfare.events.PlayerJoin.onPlayerJoin(PlayerJoin.java:47)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at org.bukkit.plugin.java.JavaPluginLoader$1.execute(JavaPluginLoader.java:425)
... 14 more