java.lang.AbstractErrorMethod

java.lang.AbstractMethodError
    at appeng.me.GridNode.FindConnections(GridNode.java:236) ~[GridNode.class:?]
    at appeng.me.GridNode.updateState(GridNode.java:147) ~[GridNode.class:?]
    at li.cil.oc.common.EventHandler$$anonfun$scheduleAE2Add$1.apply$mcV$sp(EventHandler.scala:51) ~[EventHandler$$anonfun$scheduleAE2Add$1.class:?]
    at li.cil.oc.common.EventHandler$$anonfun$onTick$1.apply(EventHandler.scala:101) [EventHandler$$anonfun$onTick$1.class:?]
    at li.cil.oc.common.EventHandler$$anonfun$onTick$1.apply(EventHandler.scala:100) [EventHandler$$anonfun$onTick$1.class:?]
    at scala.collection.IndexedSeqOptimized$class.foreach(IndexedSeqOptimized.scala:33) [IndexedSeqOptimized$class.class:?]
    at scala.collection.mutable.ArrayOps$ofRef.foreach(ArrayOps.scala:186) [ArrayOps$ofRef.class:?]
    at li.cil.oc.common.EventHandler$.onTick(EventHandler.scala:100) [EventHandler$.class:?]
    at cpw.mods.fml.common.eventhandler.ASMEventHandler_198_EventHandler$_onTick_ServerTickEvent.invoke(.dynamic) [?:?]
    at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:51) [ASMEventHandler.class:?]
    at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:122) [EventBus.class:?]
    at cpw.mods.fml.common.FMLCommonHandler.onPreServerTick(FMLCommonHandler.java:260) [FMLCommonHandler.class:?]
    at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:536) [MinecraftServer.class:?]
    at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427) [MinecraftServer.class:?]
    at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685) [li.class:?]