ftb multicraft error

6.02 03:48:05 [Multicraft] Server stopped
06.02 03:48:05 [Multicraft] Looks like a crash, check the server console. Return value: 1
06.02 03:48:05 [Multicraft] Restarting crashed server in 2.0 seconds
06.02 03:48:05 [Multicraft] Server shut down (starting)
06.02 03:48:05 [Server] INFO at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:31)
06.02 03:48:05 [Server] INFO at net.minecraftforge.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:44)
06.02 03:48:05 [Server] INFO at java.lang.Class.forName(Class.java:348)
06.02 03:48:05 [Server] INFO at java.lang.Class.forName0(Native Method)
06.02 03:48:05 [Server] INFO at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
06.02 03:48:05 [Server] INFO at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
06.02 03:48:05 [Server] INFO at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
06.02 03:48:05 [Server] INFO at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
06.02 03:48:05 [Server] INFO You will need to add them to your server before FML and Forge will run successfully.java.lang.ClassNotFoundException: net.minecraft.launchwrapper.Launch
06.02 03:48:05 [Server] INFO We appear to be missing one or more essential library files.
06.02 03:48:04 [Multicraft] Updating eula.txt file
06.02 03:48:04 [Multicraft] Loaded config for "Custom | Custom Jar"
06.02 03:48:04 [Multicraft] Starting server!