Hello, I am crashing when trying to use the utility router in a multiplayer server. It opens up fine in a single player test world but instantly crashes the server when used in multiplayer. This is the crash report:

Description: Exception in server tick loop

java.lang.NoClassDefFoundError: net/minecraft/client/gui/GuiScreen
at mrtjp.projectred.transportation.ItemRouterUtility.openGui(items.scala:236)
at mrtjp.projectred.transportation.ItemRouterUtility.func_77648_a(items.scala:230)
at net.minecraftforge.common.ForgeHooks.onPlaceItemIntoWorld(ForgeHooks.java:454)
at net.minecraft.item.ItemStack.func_77943_a(ItemStack.java:128)
at net.minecraft.server.management.ItemInWorldManager.func_73078_a(ItemInWorldManager.java:389)
at net.minecraft.network.NetHandlerPlayServer.func_147346_a(NetHandlerPlayServer.java:556)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:60)
at net.minecraft.network.play.client.C08PacketPlayerBlockPlacement.func_148833_a(SourceFile:9)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659)
at net.minecraft.server.dedicated.DedicatedServer.func_71190_q(DedicatedServer.java:334)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)
Caused by: java.lang.ClassNotFoundException: net.minecraft.client.gui.GuiScreen
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 15 more
Caused by: java.lang.RuntimeException: Attempted to load class bdw for invalid side SERVER
at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:50)
at net.minecraft.launchwrapper.LaunchClassLoader.runTransformers(LaunchClassLoader.java:279)
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:176)
... 17 more

Fixed via cbb246d