Errors on startup - QuartzCraft

07:45:24  [SEVERE] Exception in thread "pool-1-thread-10"
07:45:24  [SEVERE] org.apache.commons.lang.UnhandledException: Plugin FakePlayersOnline v0.1.2 generated an exception while executing task 44
07:45:24 at org.bukkit.craftbukkit.v1_6_R2.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:56)
07:45:24 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
07:45:24 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
07:45:24 at java.lang.Thread.run(Thread.java:722)
07:45:24 Caused by: java.lang.NoClassDefFoundError: net/citizensnpcs/api/CitizensManager
07:45:24 at me.fromgate.fakeplayersonline.FakePlayersOnline.fillNPCList(FakePlayersOnline.java:208)
07:45:24 at me.fromgate.fakeplayersonline.FakePlayersOnline$1.run(FakePlayersOnline.java:225)
07:45:24 at org.bukkit.craftbukkit.v1_6_R2.scheduler.CraftTask.run(CraftTask.java:53)
07:45:24 at org.bukkit.craftbukkit.v1_6_R2.scheduler.CraftAsyncTask.run(CraftAsyncTask.java:53)
07:45:24 ... 3 more
07:45:24 Caused by: java.lang.ClassNotFoundException: net.citizensnpcs.api.CitizensManager
07:45:24 at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
07:45:24 at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
07:45:24 at java.security.AccessController.doPrivileged(Native Method)
07:45:24 at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
07:45:24 at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:80)
07:45:24 at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)
07:45:24 at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
07:45:24 at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
07:45:24 ... 7 more