Bukkit error

[UltimateBroadcast] Task #2 for UltimateBroadcast v1.0 generated an exception
java.lang.NullPointerException
	at me.paparazzi11.UltimateBroadcast.UltimateBroadcast.broadcastMessage(UltimateBroadcast.java:58) ~[?:?]
	at me.paparazzi11.UltimateBroadcast.UltimateBroadcast$1.run(UltimateBroadcast.java:42) ~[?:?]
	at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftTask.run(CraftTask.java:53) ~[craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at org.bukkit.craftbukkit.v1_7_R1.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:345) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:587) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:545) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:457) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
	at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit.jar:git-Bukkit-1.7.2-R0.3-b3020jnks]
[23:23:38] [Server thread/WARN]: Can't keep up! Did the system time change, or is the server overloaded? Running 3238ms behind, skipping 64 tick(s)