Error Log

[16:24:25] [Server thread/INFO]: [CraftBook] Enabling CraftBook v3.9-SNAPSHOT:3873-edf1456,master
[16:24:26] [Server thread/INFO]: [CraftBook] Loading persistent data from YAML!
[16:24:26] [Server thread/INFO]: [CraftBook] Enumerating chunks for self-triggered components...
[16:24:26] [Server thread/INFO]: [CraftBook] 1875 chunk(s) for 3 world(s) processed (29ms elapsed)
[16:24:26] [Server thread/INFO]: [CraftBook] CraftBook v3.9 Beta 3 is the latest version available, and the updatability of it is: UPDATE_AVAILABLE. You currently have version CraftBook v3.9 Beta 3 installed.
[16:24:26] [Server thread/ERROR]: Error occurred while enabling CraftBook v3.9-SNAPSHOT:3873-edf1456,master (Is it up to date?)
java.lang.NoSuchMethodError: org.bukkit.Server.getOnlinePlayers()Ljava/util/Collection;
	at com.sk89q.craftbook.bukkit.CraftBookPlugin.checkForUpdates(CraftBookPlugin.java:774) ~[?:?]
	at com.sk89q.craftbook.bukkit.CraftBookPlugin.registerGlobalEvents(CraftBookPlugin.java:679) ~[?:?]
	at com.sk89q.craftbook.bukkit.CraftBookPlugin.onEnable(CraftBookPlugin.java:433) ~[?:?]
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316) ~[craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:324) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:404) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.craftbukkit.v1_7_R3.CraftServer.loadPlugin(CraftServer.java:446) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at org.bukkit.craftbukkit.v1_7_R3.CraftServer.enablePlugins(CraftServer.java:380) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.n(MinecraftServer.java:352) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.g(MinecraftServer.java:326) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.a(MinecraftServer.java:282) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.DedicatedServer.init(DedicatedServer.java:182) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.MinecraftServer.run(MinecraftServer.java:436) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]
	at net.minecraft.server.v1_7_R3.ThreadServerApplication.run(SourceFile:628) [craftbukkit-1.7.9-R0.2.jar:git-Bukkit-1.7.9-R0.1-10-g8688bd4-b3092jnks]