Dns techpack bug

Warning: version of bspkrsCore, 6.16 is newer than request 6.15
Warning: version of bspkrsCore, 6.16 is newer than request 6.15
Adding Accesstransformer map: CoFH_at.cfg
A problem occurred running the Server launcher.java.lang.reflect.InvocationTargetException
        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:606)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.run(ServerLaunchWrapper.java:43)
        at cpw.mods.fml.relauncher.ServerLaunchWrapper.main(ServerLaunchWrapper.java:12)
Caused by: java.lang.NoClassDefFoundError: net/minecraft/world/WorldServer
        at java.lang.Class.getDeclaredMethods0(Native Method)
        at java.lang.Class.privateGetDeclaredMethods(Class.java:2615)
        at java.lang.Class.getMethod0(Class.java:2856)
        at java.lang.Class.getMethod(Class.java:1668)
        at net.minecraft.launchwrapper.Launch.launch(Launch.java:131)
        at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
        ... 6 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.world.WorldServer
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
        ... 12 more
Caused by: java.lang.IllegalArgumentException
        at org.objectweb.asm.ClassVisitor.<init>(Unknown Source)
        at org.objectweb.asm.ClassVisitor.<init>(Unknown Source)
        at org.objectweb.asm.tree.ClassNode.<init>(Unknown Source)
        at cofh.asm.ASMCore.writeWorldServer(ASMCore.java:1180)
        at cofh.asm.ASMCore.transform(ASMCore.java:175)
        at cofh.asm.CoFHClassTransformer.transform(CoFHClassTransformer.java:38)
        at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:276)
        at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:174)
        ... 14 more